The population of a late medieval Irish lordship were subject to authorities political, ecclesiastical and legal. Political authority was exercised by the clann ('family'/anglicised spelling 'clan') which should be understood as the kindred of a magnate contending for territorial lordship rather than the utopian commonwealth that is commonly supposed. These magnates exercised a dual private jurisdiction as both chief of their extended family and, in right of that, as lord of a territory within which the wider population were mere subjects. Ecclesiastical authority was exercised within the framework of the territorial dioceses created by the reforming synods of the twelfth century. By the fourteenth century these had solidified and resolved into territorial parishes whose tithes supported the benefices of rector and vicar but relics of the old order survived in titular form in the office of comharba ('successor'/ anglicised spelling 'coarb') of a defunct ecclesiastical jurisdiction now attached to a bishopric or rectory held by a cleric in major orders and in the office of airchinnech ('superior'/anglicised spelling 'erenagh') of a defunct ecclesiastical community now attached in the sense of a minor order to a chief tenancy in former lands of the community held from the local bishop by right of descent within a family. Legal authority was more diffuse in that a highly developed body of Irish customary law codified since the eighth century and encompassing concepts as advanced as negligence and as arcane as trespass by bees was administered primarily by a class of independent brithemain ('jurists'/anglicised spelling 'brehons') rather than by officers of the local lord. Unfortunately for want of records of their proceedings there will be little more to say as regards the operation of this body of law in medieval Inishowen.
The Anglo-Norman incursion blocked the development of a central authority in Ireland and so, as in much of Europe, the political map was defined by a warfare that was small-scale, private and local. Irish warfare was extraordinary only in its fluidity and while such tactics were undoubtedly well suited to the often wooded and mountainous terrain they primarily arose in response to a chronic underpopulation of the countryside. The objective of the acquisitive Irish lord was not to colonise a conquered territory with settlers but to gain access to tribute and services from a population remaining in situ. The destructive harrying of a territory brought little profit to the attacker and so the preferred method was to force submission by plundering valuable and moveable property. Herds of cattle were an obvious target resulting in running battles as herds were driven towards remote fastnesses by defenders or homeward by attackers. The forces deployed in these fluid conflicts consisted of lightly-armed foot soldiers raised from the ordinary population strengthened by a lightly-armoured cavalry raised from the nobility carrying sword, shield and over-arm lance. Heavily armed Anglo-Norman or Scottish mercenary foot soldiers were sometimes employed to provide a mobile line of defence but from the fourteenth century onwards the native lords began to erect stone castles and towers causing warfare to settle into more static forms .
The erection by the Anglo-Normans in 1301 of the enclosure castle of Northburg, now in ruins at Greencastle in the northeast of the peninsula, provoked a native response in the erection of an enclosure castle at a pre-existing high status site upon an irregular rocky outcrop at Elagh in the lowlands north of Derry, of which only the ruins of a gatehouse now remain. Numerous towers and promontory forts were subsequently erected by native lords throughout the fifteenth and sixteenth centuries and these structures can be seen to proliferate in Inishowen compared to neighbouring lordships due to the protracted struggle for lordship between the indigenous MacLochlainn family of Cenél nEoghain and the encroaching O Doherty family of Cenél Conaill . Joining the ruins of Greencastle and Elagh are those of a fourteenth or fifteenth century tower in Buncrana, sixteenth century towers in Burt, Carrickabraghy, Culmore and Inch together with the remains of several promontory forts along the northern coast. To these we may add towers marked on sixteenth and seventeenth century maps at Desertegney, Isle of Doagh, Culdaff, Derry, Fahan, Glennagiveny, Redcastle and Whitecastle of which no trace now remains . These towers and forts were sited to be intervisible, to mark boundaries and to dominate the coasts and inshore waters. Their erection owed as much to commercial reasons as to military concerns of attack and reinforcement. Foreign traders plied the coasts of the peninsula attracted by an agricultural surplus of tillage crops and pastoral animals and so these structures were sited with an eye to raising income by enforcing customs duties, tolls and fishings .
The former lordship of Inishowen is geographically well defined, occupying a peninsula girt to the north by the Atlantic Ocean, to the east by Lough Foyle (Loch Feabhail, 'Lake of the Estuary') and to the west by Lough Swilly (Loch Súilí, 'Lake of (the one with) Eyes'). To the south a massif of high ground dominates access along its isthmus to a hinterland of massifs riven by valleys, plains and tidal waters, a rugged and mountainous character becoming evident towards the north and west. The former lordship survives into modern times in the name and extent of the former administrative barony of Inishowen, missing only a southern extremity detached in the seventeenth century forming part of the 'liberties' of the English colonial city of Londonderry. Modern works often state that Inishowen does not include the lands now occupied by the modern city of Derry. This would seem to be mistaken, being based upon a mapping of seventeenth century English inquisitions as to the extent of the secular lands in the area rather than a mapping of the totality of secular and ecclesiastical lands. A straightforward reading of this totality shows that by the seventeenth century an ecclesiastical boundary between the dioceses of Raphoe and Derry bisected the area  giving strong cause to believe the area was divided politically along this boundary at the time these dioceses solidified in the twelfth or thirteenth century. This enables the recovery of the southern boundary of that part of the former lordship of Inishowen now subsumed within the liberties of Derry. In the modern landscape this would seem to follow the line of the interrupted roadway heading west from Lone Moor Road to the outer edge of the modern suburb of Creggan and thereafter running uninterrupted to the head of the Killea reservoir where it follows the modern border with County Donegal until acquiring the boundary of the former administrative barony of Inishowen. Such mapping is only made possible by reference to the minor subdivisions that survive in the guise of the modern townlands and former administrative civil parishes of the peninsula, the major subdivisions have long since fallen out of use and are rendered more elusive. Inishowen was not properly surveyed or mapped until the seventeenth century but the competing claims of O Neill and O Donnell to the overlordship of Inishowen after the defeat of the MacLochlainn family at the battle of Cameirge in 1241 resulted in the production of a text in which its major subdivisions are epitomised. This legal and administrative text entitled Ceart Uí Néill ('Right of O Neill') records the rights claimed by O Neill over the various lordships of Ulster. It survives within a seventeenth century manuscript but contains such glaring anachronism between its parts that it is clear that the text must have accrued in blocks over some considerable period prior to that time. Of present interest it locates the O Doherty family in Ard Miodhair in their ancestral homeland of Tír Conaill rather than in Inishowen and so would appear to preserve a picture of the lordship of Inishowen as it existed prior to the O Doherty annexation of the fourteenth and fifteenth centuries . Regarding Inishowen it states that:
Saorthar lucht tighe Í Néill i Inis Eóghain agus do fágbhadh trí taoisigh orra i Ó Héanna agus tugadh mur dhúthaigh dhó ó Tharbh Chinn Chasla go Tumóig Eich Í Éanna (mur a ndeachaidh a hanam eisde) rioth eich dúthaigh Í Mhaolfhabhaill i ó Thumóig Eich Í Éanna go hAlltoibh Gorma ag dul sa mBréaduigh dúthaigh Í Dhuibhdhíorma i rioth eich ó Alltoibh Gorma go hArd an Chró
'The Household of O Néill in Inis Eoghain is made free. And three chieftains were left over them: O Héanna, and he was given as estate from Tarbh Chinn Chasla to Tumóg Eich Í Éanna (where she died), a horse's run; the estate of O Maolfhabhaill, from Tumóg Eich Í Éanna to Allta Gorma entering the Bréadach; the estate of O Duibhdhíorma, a horse's run from Allta Gorma to Ard An Chró'
A lucht tighe ('household') was in origin a lord's civil and military retinue but came to mean the landholding set aside for use as his personal demesne. An examination of entries in the annals shows that O Maolfhabhaill was associated with a district named Carraic Brachaidhe in the eleventh and twelfth centuries  and O Duibhdhíorma with a district named Bréadach in the twelfth and thirteenth centuries . This provides us with the names of two of the territories outlined and dates the block of text forming the extract to sometime pre-circa 1300. We can with some confidence place the caput of Carraic Brachaidhe at Carrickabraghy on the Isle of Doagh and the caput of Bréadach at Bredagh near Moville each of which bear the anglicised placename of the district within which they lie. The text continues with a contradictory section in which Inishowen is made subject to billeting, rent and maintenance but given the nature of the text this does not invalidate the above extract as witness but would seem instead to reflect changed circumstances following the fourteenth and fifteenth century O Doherty annexation. The only other reference in the historical sources to an O Neill presence in Inishowen is to a N[iall culanach] O Neill who in 1273 is described in records of the English colony as king of Yncheun . Yncheun is presumably an early anglicisation of Inishowen but in considering the present distribution of the surnames MacLochlainn and O Neill, that Niall culanach was in 1273 engaged in conflict with the ruling branch of his own family and that the description appears in a non-native source it is not persuasive of the existence of an O Neill household in Inishowen. It seems most likely that the household referred to in the extract is in fact that of the MacLochlainn family whom, as we have seen elsewhere, in earlier times segmented from the O Neill family. That the MacLochlainn family held onto their core household lands after their defeat at Cameirge in 1241 is indicated in late thirteenth and early fourteenth century annals and ecclesiastical records which show that the family retained sufficient resources to remain active in regional political disputes and to provide the Church with two bishops of Derry. The freedom referred to in the extract included an exemption from buannacht ('billeting') accompanied by an obligation to employ a force of mercenaries  which is reflected in the epithet gallóglaigh ('foreign fighters') given as we have seen elsewhere to Diarmaid MacLochlainn killed in 1260 so securing the identification. To further analyse the extract a horse's run would seem to be a customary measure in which a landholding is defined as lying between two points. As regards the placenames given in the text:
The southern lowlands between Ard An Chró and Tumóg Eich Í Éanna are not accounted for within the text so by elimination they must form the demesne of the household holding the overlordship of all Inishowen. It follows that we can with some confidence identify this area as being the demesne of the MacLochlainn family, place their caput at the enclosure castle of Elagh lying within, apply the placename Aileach (being the Irish form of the placename of the caput) to the whole of the district and place the otherwise unknown O Heannas as a mercenary force settled upon its border with Tír Conaill.
The only ecclesiastical buildings to survive from the medieval period in the peninsula are the ruins of late medieval parish churches and chapels built on a simple rectangular plan with externally undifferentiated chancel and nave. We know from occasional mentions in historical records that churches existed at Carndonagh and Derry by the seventh century , at Fahan by the eighth century  and near Moville and Culdaff by the ninth century . None of these early medieval structures survive but those at Carndonagh, Fahan, Moville and Culdaff can be placed in continuity with the sites of the late medieval parish churches in these areas, alongside early medieval crosses and slabs still extant, while that at Derry can be identified with the site of the now vanished Dubh Regles ('Black Church') of subsequent centuries. A great many other early foundations have passed unrecorded, indicated only by early medieval crosses and slabs, old burial grounds or placename elements such as domhnach, cill or teampall (all meaning 'church'). A major ecclesiastical development in the peninsula was the erection of the ninety foot long Teampall Mór ('Great Church') in Derry in 1164 . In contemporary romanesque style with round-headed arches and recessed door openings it would have been an impressive structure but unfortunately no trace of it survives except for cruciform foundations of a chancel/choir, nave and transepts drawn on a map of 1689  and now lying underneath the eighteenth century Long Tower Catholic church since built on the site. The founder of the Teampall Mór was granted a peculiar jurisdiction over the Columban foundations of Ireland by authority of the Primate of All Ireland and the Holy See at the synod of Brí Mac Thaidg in 1158  so raising the paruchia of Colmcille into a religious order outside the jurisdiction of the territorial sees created at the earlier synods of the twelfth century. The Teampall Mór was built as the mother church of this order but its national jurisdiction did not survive the Anglo-Norman incursion and from 1247 the building found alternative use as a cathedral upon translation of the local territorial see from Ardstraw, first to Maghera and then to Derry . We know that by 1397 the Dubh Regles had become a house of Augustinian canons regular and had been joined by a Dominican priory  and later by a Franciscan priory and a nunnery  but none of these structures now survive and little more can be said about them or the communities living within.
Having dealt with the formation of the diocese and the religious houses we can now turn to the formation of parishes within the diocese. Unfortunately the medieval records of Derry diocese have not survived so we have to depend wholly upon references occurring in external sources. The earliest known record of parishes in Inishowen occurs in the Papal taxation of 1306/7  in which Inishowen outwith the cathedral parish of Templemore is formed into a rural deanery containing the six parishes of Fahan, Desertegney, Clonmany, Donagh, Clonca and Moville with Clonca containing a chapel of ease. The next enumeration occurs in a metropolitan visitation of 1397  in which the rural deanery of Inishowen is increased to nine parishes upon the inclusion of Templemore and the appearance of the previously unrecorded parishes of Culdaff and Grallagh. Greater detail is given in an English survey of 1607 preliminary to the disposession of the Catholic dioceses of western Ulster  in which Inishowen has become part of a much expanded rural deanery of Derry and is reduced to eight parishes upon the disappearance of the previously recorded parish of Grallagh. We learn that by the end of the medieval period:
While the dedications to the Blessed Virgin Mary and Saint Augustine of Hippo reflect wider influences the more numerous dedications to obscure local saints give further indication that these late medieval churches existed in succession to earlier religious foundations. The connection of Saint Patrick with Carndonagh and Saint Colmcille with Derry are both very early, being matters contained within (and so pre-dating) their seventh century hagiographies . The connection of Saint Mura with Fahan dates from his abbacy of that foundation in the seventh century but the connection of Saint Finnian with Moville is probably a fiction, referring to a sixth century bishop of a more prestigious foundation of the same name. Saint Adhomhnán is presumably the seventh century abbot of Iona bearing that name but if so his connection with Grallagh has become obscure as has the connection of Saint Colmcille with Clonmany. Of the others Saints Éigne, Muirdhealach and Buadán are all now obscure, nothing being known of them except their names . The survey notes that each parish had one rector and one vicar except for Culdaff whose rectory was united with that of Moville, which would explain the absence of Culdaff from the earliest listing. Moville and Clonca are elsewhere described as plebaniae which are believed to be parishes unusual in that they contain a benefice greater than a rectory . Though the precise nature of this greater benefice remains unknown it is tempting to treat the united rectory of Moville and Culdaff, the Moville and Clonca plebaniae and the curious intertwining of these three parishes in the north-east of the peninsula as the cryptic remains of an older ecclesiastical organisation embedded within the new. The chapel of ease recorded in Clonca in 1306/7 together with the appearance and disappearance of the parish of Grallagh between 1306/7 and 1607 would seem to offer an opaque clue to unravelling the arrangement but it is nonetheless clear that the population of Inishowen were well served by a dense network of churches and chapels.
The boundaries of the eight civil parishes subsequently employed by the English authorities as units of record and administration nesting between townland and barony in the peninsula first appear in narrative form in the Civil Survey of 1654 and thenceforward in map form as shown below. These civil parishes are named for, and so can be presumed to reflect the territorial extent of, the eight medieval ecclesiastical parishes we have been considering with the addition of a remainder known as Barr of Inch (Barr na hInse, 'Top of the Island') or Mintiaghs (Minteacha 'Mountainside Pastures') attached jointly to the civil parishes of Templemore and Clonmany, presumably reflecting a previously unrecorded ecclesiastical condominium in this barely-inhabited upland area.
It becomes immediately apparent that the pre-circa 1300 political boundary markers mentioned in Ceart Uí Néill correlate strongly with certain of the circa 1306/7 onwards ecclesiastical parish boundaries and that these in turn appear to follow a scheme converging upon the mountain Slieve Snaght (Sliabh Sneachta, 'Snow Mountain') having northern and eastern artefacts across the intrusive extents of the parishes of Donagh and Clonca. Excluding a couple of small outliers, the parish boundaries correlating with the political boundary markers pass along watercourses up to the watershed following the upslope-downslope boundary morphology usual in mountainous areas. Once at the watershed they look to have been set by line of sight across the uplands to Slieve Snaght in accordance with the generally vague delineation of wastes in medieval times, the two southern sightlines being later resolved onto watercourses. The map would thus seem to offer opportunities to leverage developments between an underlying political scheme pre-circa 1300 and an overlying ecclesiastical scheme circa 1306/7 onwards. The eastern artefact is continued to Slieve Snaght by resolution onto upland watercourses and so conforms to the scheme in its essence, the intrusive southern extent of the parish of Donagh existing only for want of suitable watercourses in this area. The northern artefact, however, is terminated sharply by the intrusion of the parish of Clonca in a lowland area around Grallagh and so demands explanation. By 1609 the erstwhile parish of Grallagh seems to have survived vestigially as a territorial discontinuity within the parish of Clonca by which the erenagh proportion of tithes arising from seven quarters of land were ringfenced exclusively for the MacLochlainn erenagh family of Grallagh rather than pooled among the several erenagh families of the parish . Seven quarters joined to the two quarters the family held outright can be mapped onto the matrix of modern townlands in this area to give Grallagh a probable extent that infills the intertwining of the parishes of Clonca and Culdaff to continue the northern artefact along a modern townland boundary towards Slieve Snaght as far as the eastern angle of Trawbreaga Bay. A ninth century source places the medieval church site in modern Carndonagh outside Bréadach  so by positing the resumption of an upslope-downslope boundary morphology we can resume the artefact along the course of the Donagh river east of modern Carndonagh up to its headwaters on Slieve Snaght and so recover the political scheme to what appears to be its pristine state. What emerges from this analysis is that in its east-west extent the parish of Donagh has from the outset cut across the underlying political scheme and that in its east-west extent the parish of Clonca has cut across the underlying political scheme intermittently. In considering events known to have occurred between the dates of the political and ecclesiastical schemes it seems likely that the western boundary of the parish of Donagh reflects the western boundary of the Anglo-Norman manor of Northburg established upon erection of Northburg castle in 1301 , so preserving at least in part the westernmost extent of the intruded Anglo-Norman earldom of Ulster.
Of the manor of Northburg all that is known is that the Anglo-Norman de Burgo earls of Ulster were content to let the whole of the lands to native tenants. By 1310 the de Burgos had intruded themselves into various episcopal lands in Inishowen and Derry and claimed lay patronage over certain ecclesiastical benefices, presumably including those of the church of Saint Mary Northburgh endowed by them in that year (which can perhaps be identified with the church ruins at Templemoyle noted above). In 1316 the castle of Northburg fell for a time to the de Bruce invaders from Scotland but by 1333 the manor had been lost to the earldom . In the wake of the Anglo-Norman collapse the O Doherty family seem to have extended their sphere of influence from their homeland in Tír Conaill into Inishowen so that by 1339 the chief of the O Doherty family was lord of Inishowen in all but name  and by 1413 enjoyed unequivocal possession of the lordship . I can find no local instances of the Black Death following its advent in eastern Ireland circa 1348 but it must surely have had an effect. In 1375 the death of the chief of the MacLochlainn family is noted  but thereafter the family pass unnoticed by the annalists. The vanquishing of the Cenél nEoghain interest in the peninsula would seem by 1514 to have led to a realignment in the legal position so that it was accepted that O Doherty held the lordship of Inishowen ultimately from O Neill but immediately from O Donnell . An analysis of the pattern of segmentation of the various territorial groups that make up the O Doherty family genealogy in the seventeenth century O Clery Book of Genealogies indicates that the family did not migrate across the southern isthmus of the peninsula as assumed in modern histories but instead spread south from a maritime base located in the north of the peninsula around Malin and the Isle of Doagh, where their deepest and most complex branching groups are to be found . This venture would seem to be conjoined with that of the Scottish MacSweeney galloglas family who came to hold the lordship of Fanad on the western shore of Lough Swilly, as in doing so the MacSweeneys claim to have held the trian medhonach ('middle third') of Inishowen around that time . The most recently segmenting group is that of Greencastle whose genealogy consists of five simple stems found also within the more complex branching groups of Glennagannon and Malin indicating that in the seventeenth century the Greencastle group had been fairly recently abstracted from longer established groups to the west. A widespread and quite late O Doherty migration into the east of the peninsula is specifically confirmed by an English state paper of 1601 in which an O Doherty in Dunowen near Culdaff can be cross referenced to the Inch Island genealogy , an English inquisition of 1602 in which an O Doherty in Gleneely and and O Doherty in Tremone can also be cross referenced to the Inch Island genealogy  and in general terms by the O Doherty surrender and regrant of 1588 in which the omission of the area between Culmore and Greencastle indicates the existence of another interest on the eastern coastline . We have seen above that in its east-west extent the parish of Clonca has cut across the underlying political scheme into Grallagh intermittently so that the fluctuating ecclesiasical status of Grallagh from chapel of ease within Clonca in 1306/7 to separate parish by 1397 and back to chapel of ease within Clonca by 1607 likely reflects the fluctuating political status of this area over time. This allows us to create a tentative history of the area from its loss to the Anglo-Normans by 1306/7 as they entered the Malin peninsula and saw Grallagh attached to Clonca to its recovery by the MacLochlainn family who saw Grallagh created a parish by 1397 to its coming under the control of the O Doherty family who saw Grallagh reattached to Clonca by 1607. In 1601 the towers of Redcastle and Whitecastle on the east coast were under MacLochlainn control according to English state papers . Neither of these structures survive but their general appearance can be ascertained from sketches on a map (pictured above) based upon a survey of Inishowen carried out circa 1609 . These sketches are not schematic symbols as found on other maps of the period but reflect the appearance of structures still surviving and so can be broadly relied upon as evidence for the appearance of those structures that no longer survive. Whitecastle is drawn as a tall rectangular tower with gabled roof and dormer windows or battlements rising above the wall-line. A narrow tower attached to one corner allows the occupants a field of fire across the entrance to the main tower and a short round tower forms part of an outer enclosure. Redcastle is drawn as a simple circular tower with battlements. In considering the evidence for a late O Doherty migration into the east of the peninsula it becomes apparent that this late MacLochlainn lordship centred on Redcastle and Whitecastle was the last vestige of a MacLochlainn lordship of Bréadach, itself the last vestige of the MacLochlainn lordship of Inishowen, recovered from the Anglo-Normans and held tenaciously against the encroachments of the O Doherty family.