The lands of Bedlay or Ballayn were possession of the
Bishops of Glasgow. The grant of land to the diocese was confirmed by
David I and again by
William I in 1180.
Bishop Cameron is reported to have had a castle or house on this site. In 1580, James Boyd of Trochrig, then the titular Protestant Archbishop of Glasgow, granted the lands to his kinsman,
Robert Boyd, 4th Lord Boyd of Kilmarnock. He built the original Bedlay Castle soon after, on the end of a volcanic crag above the Bothlyn Burn. The Boyds held the castle until 1642, when James, 9th
Lord Boyd sold it to the advocate
James Roberton, grandson of John Roberton, 9th Laird of
Earnock, later Lord Bedlay. The Robertons extended the castle, and held the property until 1786. Since then the castle has been owned by a number of people, including the Campbells of Petershill, who built a family mausoleum in the grounds. Bedlay is still privately owned and occupied as a house. As of May 2007, Bedlay Castle was up for sale. ==The castle==