On his father's side, he was the grandson of King Edward III and Philippa of Hainault, and on his mother's side, the grandson of Peter the Cruel, King of Castile and León, and his favourite mistress, María de Padilla (died 1361).

Harriss as an indication that Richard's father and brother did not recognize him as a full blood relative, and that he may have been the child of an illicit liaison between his mother and the king's half-brother John Holland.

[8] From April 1403 to October 1404, Richard commanded a small force defending Herefordshire against the Welsh rebel leader Owain Glyndŵr, but otherwise performed no notable military service.

[13] Perhaps partly for this reason, Richard conspired with Lord Scrope and Sir Thomas Grey to depose Henry V of England and place his late wife Anne's brother Edmund Mortimer, 5th Earl of March, on the throne.

The Southampton Plot is dramatised in Shakespeare's Henry V, and in the anonymous play, The History of Sir John Oldcastle.

[13] In the parliament of 1461, King Edward IV had the sentence that had been passed on his grandfather, Richard, Earl of Cambridge, annulled as "irregular and unlawful".

Anne was a niece of Richard's stepmother Joan Holland,[16] and the granddaughter of his first cousin, Philippa of Clarence.

It brought Richard no financial benefit, since Anne's only income was an annuity of £50 granted for her maintenance by Henry IV in 1406.

[24] After Richard’s death in 1415, his second wife, Maud Clifford, is said to have lived in "great state" at Conisbrough Castle and elsewhere.