[1] As the chaplain of Robert de Brus, he was elected by the chapter of Whithorn Cathedral to replace the recently deceased Henry of Holyrood as Bishop of Galloway, sometime before 13 January 1294.
[1] Although naturally better disposed to the Bruces than Balliols, his exact role during the turbulence of the First War of Scottish Independence is not clear; after the deposition of Balliol by King Edward I of England, he was co-operative with the English crown, both in his role as a senior inhabitant of the Kingdom of Scotland and as a suffragan of the Archbishop of York.
[4] He spent a great deal of time in this period both in Galloway, and in England, and was a close associate of John de Halton, Bishop of Carlisle.
[5] Bishop Thomas however had spent a lot of time in the post-Bannockburn kingdom, attending the Ayr assembly of 27 April 1315, where he added his seal to a declaration about the Bruce succession; he added his seal to another pro-Bruce document at some point between October 1314 and November 1316, and attended the Scone parliament of 3 December 1318.
[6] His date of death is unknown exactly, but it was after 4 April 1324, and had occurred by 23 September 1326, when his successor Simon de Wedale was elected to succeed him.