Church and chapel data from The Religious census of 1851 : A Calendar of the returns relating to Wales, Vol 11, North Wales. Ed. by Ieuan Gwynedd Jones, UWP, 1981. The names given towards the end of each entry are those of the informants.
Trewalchmai Parochial Chapelry; Statistics; Area 1700 acres; Population 369 males, 406 females, total 775
Trewalchmai Parochial Chapel (Diocese of Bangor) Attendance - morningn 34 +15 scholars William Evans, Curate
"Gwalchmai Baptist Chapel is a typical small chapel ............... The congregation was formed in 1889 and the chapel opened in the following year........." coflein
"Gwalchmai Methodist Chapel was built in 1789, rebuilt in 1810, 1849 and rebuilt for a third time in 1925. ........." coflein
Moriah Ind Chapel, Gwalchmai - on geograph.org.ukand "......... cause at Gwalchmai-isaf established in 1844 and Moreia chapel opened in 1847. This was modified in 1892 and rebuilt/enlarged in 1902 ......." coflein
Rees, Thomas & John Thomas Hanes Eglwysi Annibynnol Cymru (History of the Welsh Independent Churches), 4 volumes (published 1871+). The Gwalchmai section (in Welsh) has been extracted - with translation by Eleri Rowlands (Aug 2014)
Trewalchmai Tithe Apportionment 1840-1841 - details of extant records on Archives Network Wales
"Copy Tithe Apportionment for the parish of Trewalchmai, Anglesey, 1840-1841, together with map. Includes cereal prices and names of owners and occupiers of land"