In 1870-72, John Marius Wilson's Imperial Gazetteer of England and Wales described Portskewett like this:
PORTSCUETT, Portskewit, or Porth-is-Coed, a parish in Chepstow district, Monmouth; on the Severn'sestuary, the Julian way, and the Great Western railway, at the Junction of the Bristol and South Wales Union railway, 4¼ miles S W by S of Chepstow. It has a station with telegraph at the railway junction; and its post town is Chepstow. Acres, 1, 779; of which 720 are water. Real property, £2, 110. Pop., 175. Houses, 36. The property is all in one estate. The living is a rectory, united with the rectories of St. Pierre and Sudbrook, in the diocese of Llandaff. Value, £402.* Patron,Lewis, Esq.
A Vision of Britain through Time includes a large library of local statistics for administrative units. For the best overall sense of how the area containing Portskewett has changed, please see our redistricted information for the modern district of Monmouthshire. More detailed statistical data are available under Units and statistics, which includes both administrative units covering Portskewett and units named after it.
GB Historical GIS / University of Portsmouth, History of Portskewett in Monmouthshire | Map and description, A Vision of Britain through Time.
Date accessed: 31st May 2016
Click here for more detailed advice on finding places within A Vision of Britain through Time, and maybe some references to other places called "Portskewett".