Sir William Moore, 1st Baronet, PC (NI), DL was a Unionist member of the British House of Commons from Ireland and a Judge of Ireland, and subsequently of Northern Ireland. He was created a Baronet in 1932.

The 1921 Birthday Honours were appointments by King George V to various orders and honours to reward and highlight good works by citizens of the British Empire. The appointments were made to celebrate the official birthday of the King, and were published on 3 and 4 June 1921.