"LLANISHEN, a parish in the upper division of the hundred of Ragland, county Monmouth, 6 miles S.W. of Monmouth, its post town, and 7 from Chepstow. The village consists of a few farmhouses. The tithes have been commuted. The living is a perpetual curacy in the diocese of Llandaff, value £64. The church is dedicated to St. Dennis. The parochial charities produce about £22 per annum." [Description(s) from The National Gazetteer of Great Britain and Ireland (1868)
Church and chapel data from The Religious census of 1851 : A Calendar of the returns relating to Wales, Vol 1, South Wales.Ed. by I.G Jones, & D. Williams. UWP, Cardiff, 1976. The names given towards the end of each entry are those of the informants. Check with Gwent RO to see what extant records are held, and possible names of chapels/churches established after 1851.
Llanishen Parish; Statistics; Area 1742 acres; Population 177 males, 174 females, total 351
Llanishen Parish Church Attendance (Average) - morning 50/60, afternoon 80/100 " A small old church and very damp. March 30 1851 was mid-Lent Sunday and many people of this parish absent themselves from Church and visit their friends that day. There is no Convenient place in this little church for Sunday Scholars" 1 service in English Henry Warrilow, Incumbent Minister
Family Search have an interactive map called "England and Wales Jurisdictions 1851" showing parish (and other) boundaries with optional background maps such as Ordnance Survey. There is also a Search facility, do read the guidance notes to get maximum benefit from this useful resource. See here for further background information to assist in the interpretation of this data
Kain, R.J.P., Oliver, R.R., Historic Parishes of England and Wales: an Electronic Map of Boundaries before 1850 with a Gazetteer and Metadata [computer file]. Colchester, Essex: History Data Service, UK Data Archive [distributor], 17 May 2001. SN: 4348. Here is a gazetteer/finding aid plus a set of overview maps to accurately identify the position of parishes within the county.
You can see maps centred on OS grid reference SO475031 (Lat/Lon: 51.72415, -2.761463), Llanisien / Llanishen which are provided by: