The title was originally held by the deRos family until the death of the eleventh Baron in 1508, when it was inherited by his nephew, Sir George Manners.
The abeyance was terminated in favour of her eldest daughter, Una Mary Ross (née Dawson) in 1943, and again went into abeyance upon her death in 1956.
Una Mary Dawson, 26thBaronessdeRos (1879-1956) (abeyance terminated 1943; abeyant 1956)
The title of Baron deRos (pronounced "Roose") is the most ancient baronial title in the Peerage of England.
The title was originally held by the deRos family until the death of the eleventh Baron in 1508, when it was inherited by his nephew, Sir George Manners.
The abeyance was terminated in favour of her eldest daughter, UnaRoss (née Dawson) in 1943, and again went into abeyance upon her death in 1956.