After Archibald, 5th Earl of Morton and 8th Earl of Angus died without heir, the Morton titles settled on Sir William of Lochleven. Sir William was 7th from Sir Henry of Lugtoun and Lochleven, younger brother of Sir James of Dalkeith. 

Sir William is best remembered for his role as jailer of Mary Queen of Scots during her confinement at Lochleven Castle. 

Sir William's eldest son disappeared in travel circa 1548, so the Morton possessions devolved to Sir William's grandson upon his death on September 27, 1606.

• Birth: 1540
• Death: 27 SEP 1606
  
  Father: Robert (Sir) (of Lochleven) Douglas
  Mother: Margaret (of Mar) Erskine
  
  Marriage 1 Agnes (of Rothes) Leslie
  • Married: 19 AUG 1554
  Children
  1. James (of Morton) Douglas = x3
  2. Archibald (Sir) (of Killour) Douglas 
  3. George (Sir) (of Kirkness) Douglas
  4. Christian (of Morton) Douglas = (2) Alexander 1st Earl of Home
  5. Eupheme (of Morton) Douglas = Sir Thomas Lyon of Auldbar, Master of Glamis
  6. Agnes (of Morton) Douglas = Archibald Campbell, 7th Earl of Argyll
  7. Elizabeth (of Morton) Douglas = Francis Hay, 9th Earl of Errol
  8. Jean (of Morton) Douglas = ?
  9. Mary (of Morton) Douglas = Sir Walter Ogilvy, 1st Lord Ogilvy of Deskford
  10. Margaret (of Morton) Douglas = Sir John Wemyss, of Wemyss 
  11. Robert (Master of Morton) Douglas = Jean Lyon of Glamis

See also The Earls of Morton