William Sinclair (1410–1480), 1st Earl of Caithness (1455–1476), last Earl (Jarl) of Orkney, 2nd Lord Sinclair and 11th Baron of Roslin was a Norwegian and Scottish nobleman and the builder of Rosslyn Chapel, in Midlothian.
- Occupation
- jurist, architect, judge
- Position held
- Member of the Parliament of Scotland, Earl of Orkney, Lord Chancellor of Scotland
- Citizenship
- Scotland
- Born
- 1410
- Died
