Biography

He was the son of Alexander Cunningham, 5th Earl of Glencairn

Alexander Cunningham, 5th Earl of Glencairn

Alexander Cunningham, 5th Earl of Glencairn was Scottish nobleman and Protestant reformer, prominent in the Scottish Reformation.-Biography:...

 and Janet Hamilton, daughter of James Hamilton, 1st Earl of Arran

James Hamilton, 1st Earl of Arran

James Hamilton, 1st Earl of Arran and 2nd Lord Hamilton was a Scottish nobleman and first cousin of James IV of Scotland.-Biography:...

. He married sometime before 24 August 1549 to Janet Gordon of Lochinvar (died 18 November 1596). She was the daughter of Sir John Gordon of Lochinvar and Margaret Crichton. They had the following children:

• James Cunningham, 7th Earl of Glencairn
  James Cunningham, 7th Earl of Glencairn
  James Cunningham, 7th Earl of Glencairn was a Scottish peer and member of the Privy Council of Scotland.-Early life:The eldest son and heir of William Cunningham, 6th Earl of Glencairn by his spouse Janet, daughter of Sir John Gordon of Lochinvar, James was engaged in the notorious Raid of Ruthven...
  
  
• John Cunningham, Laird of Ross
• Lady Jean Cunningham who married George Haldane of Gleneagles (died 18 October 1574). After his death she married Roger Kirkpatrick of Closeburn. After his death she married Robert Fergusson, 9th Laird of Craigdarroch (died about 1613).
• Lady Margaret Cunningham who married Sir Lachlan Mor Maclean
  Sir Lachlan Mor Maclean
  Sir Lachlan Mór Maclean or Lachlan the Great, was the 14th Clan Chief of Clan MacLean from late 1573 or early 1574 until 1598.Mór or Mor translates as great in English, or magnus in Latin, when added to a name in Scottish Gaelic....
  
   of Duart (died 5 August 1598)
• Lady Elizabeth Cunningham who married (1) in 1579 to James Crawford of Auchinames. After his death she married Alexander Cuninghame, 5th Laird of Craigends. Elizabeth died before 7 September 1614.
• Lady Susannah Cunningham who married John Napier of Kilmahew

William died between 1576 and 24 February 1579/80.