Llancillo is a civil parish in south-west Herefordshire, England, and is approximately south-west from the city and county town of Hereford. The parish borders Wales at the south in which is the nearest town, Abergavenny, to the south-southwest. In the parish is the isolated Grade II* listed 11th-century Church of St Peter.

History Llancillo is not mentioned in Domesday Book. Following the Norman Conquest, Roger de Lacy, son to Walter de Lacy, held the parishes of Rowlestone and Llancillo from Henry de Ferrers, the tenant-in-chief to king William I. Llancillo was part of Ewyas Lacy hundred, and was held under Roger de Lacy, and through him in turn by the Normans William and Osbern who constructed the castle at Llancillo.Lovell, Clementine (2004), Llancillo Hall, archaeological monitoring, Archenfield Archaeology Ltd. Retrieved 29 May 2022

'Llan' in this context means variously church, land, building or enclosure, or those attributes applied to a religious building or estate, and is an indication here of a pre-Norman church. 'Cillo' could be a corruption of an earlier saint's name, perhaps St Sulfyw (Sylvius). Llancillo in c.1150 was written as Lann Sulbiu, or Lannsuluui, or Ecclesia Sancti Sulbiu (Church of St Sulbiu); in 1182, Lantelio; in 1296, Lansilio, in 1323, Lanciliou; in 1399, Lancelio; in 1770, Lansyllo or Llancillo; in 1733 as Llansilo; in 1754, Lansillo; and in 1840 as Llannsillo or Llancillo.“Lann”, Wiktionary. Retrieved 13 May 2022Mathúna, Liam Mac , Observations on Irish "Lann" '(Piece of) Land; (Church) Building' and Compounds, Vol. 48, (1997), Royal Irish Academy, pp. 153-160Bannister, Arthur T.; The Place-names of Herefordshire Their Origins and Development (1916) p.188Rees, William Jenkins MA, FSA (1840) The Liber Landavensis, Llyfr Teilo, or The ancient register of the Cathedral Church of Llandaff… (The Book of Llandaff), published for the Welsh Manuscripts Society, Oxford, 1893, pp.151, 152, 405, 406"Llancillo" in Transactions of the Bristol and Gloucestershire Archaeological Society (1916), pp.158,159Ekwall, Eilert (1936); The Concise Oxfordshire Dictionary of English Place-names, Oxford University Press, 4th ed. (1960), p.301 "Place-Names", Herefordshire Through Time, Herefordshire Council. Retrieved 29 May 2022 In the 1840 transcription and translation of the 12th-century Liber Landavensis... (Book of Llandaff), the sections on Llancillo state that the Early Middle Ages' king Meurig, who was patron for the Celtic Llandaff Cathedral, today in Cardiff, gave Llancillo to the cathedral and its bishop and saint Ufelwy, "for the redemption of his soul, to God, and the saints Dubricius and Teilo". St Dubricius is interred and St Telio's relics held at Llandaff. Llancillo was given in perpetuity to Llandaff, its land extent laid out in text which bounded this through a description of watercourses.

In the first half of the 17th century was recorded an ironworking forge at Llancillo (), using power from a tributary of the River Monnow at the south of the parish, including a leat, "weirs, ponds, dams, watercourses, houses and buildings". An early lease-out dates to 1637, under the Scudamore family, who then owned the forge, outright or in partnership, until at least 1778. By 1677 the forge was producing 150 tons of wrought iron a year; it obtained pig iron from Llanelly and sold the resulting refined wrought iron in Monmouth. In 1810 it is noted as a charcoal forge, and is drawn on Ordnance Survey and tithe maps from 1814, to 1839 when it is shown as disused. Slag and clinker waste is still evident on the site.Coates, S. D., Tucket, D. G. (1978) Water-mills of the Monnow and Trothy, Monmouth District Museum Services, pp.46, 47. Retrieved 29 May 2022"Herefordshire forges", Herefordshire Through Time, Herefordshire Council. Retrieved 29 May 2022

In the 19th and 20th century, Llancillo is described in directories as a small parish and village on the river Monnow, bordering Monmouthshire, south-southwest from the village of Abbey Dore, north-east from Abergavenny, and south-west from Pontrilas railway station on the Newport, Abergavenny and Hereford Railway which later, after amalgamation, became a branch of the Great Western Railway. The parish was in the Webtree hundred before 1860, and after, that of Ewias Lacy (Ewyas Lacy), and in the rural deanery of Weobley and later, in the 20th century, the rural deanery of Abbey Dore, both in the diocese and archdeaconry of Hereford. Llancillo was in the Abbey Dore Union—poor relief and joint parish workhouse provision set up under the Poor Law Amendment Act 1834—and the petty sessional division and county court district of Hereford. The parish was part of the polling district of Longtown, but by 1890 was part of the Pontrilas and Orcop polling district.Llancillo in Post Office Directory of Herefordshire 1856Llancillo in History, Topography & Directory of Herefordshire, 1858, pp.223, 224Llancillo in Post Office Directory of Gloucestershire, Herefordshire, Shropshire, and the City of Bristol, 1863, p.559Wilson, John Marius, Llancillo, Imperial Gazetteer of England and Wales 1870, A Vision of Britain through Time, Great Britain Historical GIS. Retrieved 29 May 2022Llancillo in Littlebury’s Directory and Gazetteer of Herefordshire (1876)Llancillo in Llancillo Kelly's Directory of Herefordshire, 1885 p.1205Llancillo in Jakeman & Carver's Directory of Herefordshire, 1890 p.544Llancillo in Kelly's Directory of Herefordshire & Shropshire, 1895. (Part 1 Herefordshire) p.132Llancillo in Kelly's Directory of Herefordshire and Shropshire, 1905Llancillo in Kelly's Directory of Herefordshire, 1913, p.151Llancillo in Kelly's Directory of Herefordshire and Shropshire, 1917

The parish church of St Peter is described before 1870 as "a very old stone building" and "old, plain, and good", which included a nave, chancel, south porch, and a small bellcote at the west with one bell. By 1876 it was in a bad state of repair and unfit for divine service, and nine years later still "dilapidated and disused". There was no road to the church, the congregation attending services at Rowlestone and in 1890, as the parish was almost without population, it was not intended to restore it. However, the church was restored in 1895 and was described as "old and curious, in the Early English style", and now having two bells. In the churchyard were reported tombstones to the Scudamore family. The parish register dates to 1728. The parish living was consolidated with that of the vicarage of Rowl[e]ston, although during parts of the 1860s and 1870s being a perpetual curacy (an office supported by stipend rather than tithes or glebe). While a vicarage, the incumbent was supported by of glebe—an area of land used to support the parish church and priest—and a residence, and variously at times advowson by patrons from Eccles, Carlisle and Southampton.

Lords of the manor in the 19th century were members of the Scudamore family whose seat was Kentchurch Court, to the east, who were parish chief landowners alongside variously the Price family of Llancillo Hall and the Scottish Union and National Insurance Company of London. Lord of the manor between the 1870s and the First World War was Edward Lucas-Scudamore ((1853–1917), later Colonel in the Hereford Regiment of Militia and JP, of the Castle Shane Estate, County Monaghan, and Cap House at Pontrilas. Parish land was of including of water, and is sandy over a subsoil of red sandstone on which was grown wheat, barley roots and oats. Population in 1851 was 70; in 1861, 74; in 1871, 88 (with 14 inhabited houses); 1881, 62 (with 11 families or separate occupiers); 1891, 60; 1901, 66; and 1911, 52. In the last half of the 19th century there were typically six or seven farmers listed in directories, and at least one farm bailiff. The parish clerk was occasionally mentioned as resident after 1856, while in 1890, there was listed an assistant overseer for the parish who lived at the Carpenter's Arms in Abergavenny. Letters were delivered and received through the post town Abergavenny via Pandy, and from the 1880s the nearest money order and telegraph office was at Pontrilas. Up to 1876 there was no school in the parish, but a school board had been formed in 1875 for the united district of Rowlstone, Walterstone, and Llancillo. By 1885 the school board was in place and children attended the new board school at Walterstone. By 1905 the school was now an elementary school."Kentchurch Court and History", Kentchurch Court. Retrieved 29 May 2022"Lucas Becomes Lucas-Scudamore", Castleshane History. Retrieved 29 May 2022

Geography Llancillo parish boundary is of triangular footprint, at its greatest distance north to south, east to west, and covers an area of approximately ."Llancillo", Citypopulation.de. Retrieved 15 May 2022 Adjacent Herefordshire parishes are Walterstone at the west, Longtown at the north-west, and Rowlestone at the north, with the Monmouthshire community of Grosmont at the south. The parish is rural, of six farm complexes, fields, managed woodland and coppices, watercourses, ponds, and residential properties. Flowing west to east at the south of the parish is the River Monnow tributary to the River Wye, this to the south-east at Monmouth. The Morrow at its west forms the border with Monmouthshire. From the north-west of the parish flows tributaries to a stream with woodland margins, which passes Llancillo Church and Llancillo Court Farm, and flows to the south-east of the parish to join the River Morrow. There is a group of unnumbered minor roads at the north, and another at the south; no road connects the north of the parish to its south. A north-east to south-west through road at the north runs from the village of Rowlestone towards Pandy in Monmouthshire, these both outside the parish. From the A465 Abergavenny to Hereford road at the southern edge of the parish, a road runs north; it crosses the River Morrow by a one lane road bridge, and immediately splits to two circuitous routes: one to Llancillo Court Farm and Llancillo Church nearly north-east, the other to Llancillo Hall Farm north-west. These roads bridge the Welsh Marches railway line which runs almost entirely through the south of the parish. All other routes are bridleways, farm tracks, property entrances and footpaths.Extracted from “Llancillo”, Grid Reference Finder. Retrieved 15 May 2022Extracted from “Llancillo”, Google Maps. Retrieved 15 May 2022Extracted from “Llancillo”, GetOutside, Ordnance Survey. Retrieved 2 May 2022.Retrieved 15 May 2022Extracted from "Llancillo", OpenStreetMap. Retrieved 15 May 2022

Running east to west through the parish is part of the Golden Valley Pilgrim Way, which and passes St Peter's Church. The Golden Valley Pilgrim Way is a circuitous footpath and road route through western Herefordshire, beginning and ending at Hereford Cathedral. St Peter's Church is also on the route of the Chester to Cardiff Marches Way footpath.Golden Valley Pilgrim Way, British Pilgrimage Trust. Retrieved 28 May 2022"St Peter's, Llancillo, Herefordshire", Friends of Friendless Churches. Retrieved 27 May 2022

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