Auchintoul fought for the Montrosians in the Civil War. He was captured at Philiphaugh and, by the direct intervention of Lieutenant General David Leslie, was dealt with leniently compared to other prisoners (most of whom were executed after the battle). With David Leslie vouching for him directly, Auchintoul avoided execution. When David Leslie's petition was read, by Argyll among others, Auchintoul was spared (along with Lord Gray), but was banished from Scotland for life.