Elizabeth de Burgh, Duchess of Clarence, suo jure 4th Countess of Ulster and 5th Baroness of Connaught was a Norman-Irish noblewoman who married Lionel of Antwerp, 1st Duke of Clarence.

Lionel of Antwerp, Duke of Clarence,, was an English prince, Earl of Ulster jure uxoris from 1347, Duke of Clarence from 1362, Guardian of England in 1345-1346, Lord Lieutenant of Ireland in 1361-1366, Knight of the Garter from 1361, second surviving son of King Edward III of England and Philippa of Hainault. He was named after his birthplace, at Antwerp in the Duchy of Brabant.