English: The armorial achievement of Jeffrey Thomas, agnatic descendant of Sir William ap Thomas, the "Blue Knight of Gwent" (obit 1445).

The arms are those recorded in the 1620 Visitation of Cornwall, ascribed to the Thomases of Lelant, Thomases of Crowan, Thoms, and the Bosarvanes of St Just families, all patrilineally descended from "Richard Thomas gent. of Wales" who settled in Lelant in Cornwall some time early in the sixteenth century, where he married the daughter and heiress of John Hicks of Lelant. The motto and crest are those of the descendants of Rev. William Courtenay Thomas, the current armiger's grandfather.

The 1620 Visitation records state "This coate of Pr pale nebule Ar. B. was ye coate armor of Sr Willm ap Thomas, from whom this familye chalengeth to be descended."

Sir William ap Thomas was himself a member of the dispossesed pre-Norman royal family of Gwent, and was married to Gwladys, daughter of Sir Dafydd ap Llewelyn ap Hywel, or "Davy Gam", who was an heir to the Kingdom of Brycheiniog. Davy Gam fell at Agincourt along with Gwladys' first husband.

Sir William also is believed to have fought at Agincourt, where he was knighted on the field.

The current earls of Pembroke (Herbert family) are descended from an illegitimate grandson of Sir William ap Thomas.

Copyright resides with the poster, however the artwork was created by Mr Ljubodrag Grujic.