In 1870-72, John Marius Wilson's Imperial Gazetteer of England and Wales described Bryn Y Beirdd like this:
BRYN-Y-BEIRDD, a hamlet in Llandilofawr parish, Carmarthen; near Llandilofawr. Real property, £921. Pop., 386.
The location is that of "Cwrt-bryn-y-beirdd", as more clearly marked on the modern 1:25,000 map. Samuel Lewis's Topographical Dictionary of Wales (1849) provides a more detailed description: "BRYN-Y-BEIRDD, a hamlet, in that part of the parish of Llandilo-Vawr which is in the hundred of Iscennen, in the union of Llandilo-Vawr, county of Carmarthen, South Wales, 4 miles (S. E. by S.) from Llandilo-Vawr; containing 386 inhabitants. A farmhouse in this hamlet, called Cwrt Bryn-y-Beirdd, is supposed to have been the collegiate residence of the bards attached to the royal palace and castle of Carreg-Cennen" (http://www.british-history.ac.uk/report.aspx?compid=47804, accessed 7/3/2011).
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 Bryn Y Beirdd has changed, please see our redistricted information for the modern district of Carmarthenshire. More detailed statistical data are available under Units and statistics, which includes both administrative units covering Bryn Y Beirdd and units named after it.
GB Historical GIS / University of Portsmouth, History of Bryn Y Beirdd in Carmarthenshire | Map and description, A Vision of Britain through Time.
Date accessed: 11th March 2014
Click here for more detailed advice on finding places within A Vision of Britain through Time, and maybe some references to other places called "Bryn Y Beirdd".