[1] He was the three-times great-grandson of Walter Devereux, 1st Viscount Hereford, through his second wife, Margaret Garneys.
His paternal grandparents were MP George Devereux (d. 1682) of Vaynor Park, Montgomeryshire and Bridget Price.
A senior line of descendants of Sir George had held the title from 1700 to the death of their last male-line member in 1748.
The Baronet was the fourth son of Walter Devereux, 1st Viscount Hereford by his second wife.
She was a daughter of Richard Mytton of Pontyscowryd and Garth, High Sheriff of Montgomeryshire and Dorothy Wynn.