John Ogilvie was born to a Calvinist Scots baronial family, sent to the Continent at thirteen for advanced study (his Calvinist father wished to keep him from English Catholic influence), and converted to Catholicism at seventeen at the Scottish College at Olomouc in Moravia after exposure to the deep theological literature of the Counter-Reformation. He entered the Society of Jesus at Brno in 1599 and was ordained priest in Paris in 1610.
He served briefly at Rouen and then returned to Scotland clandestinely in 1613 as part of the small group of Jesuits attempting to minister to the surviving Scottish Catholics — who, after the brutal Edwardian and Jacobean reforms, were down to perhaps a few thousand recusants in the entire kingdom. He ministered in Edinburgh and Glasgow under the alias 'John Watson.'
He was betrayed in Glasgow in October 1614, arrested, and subjected to twenty-six days of sleep deprivation — a method designed to break his will without leaving physical marks that would generate sympathy. He refused to renounce papal authority, to reveal the names of Catholics he had served, or to acknowledge James VI as supreme head of the Church. He was hanged at Glasgow Cross on March 10, 1615, the only Catholic priest publicly executed in post-Reformation Scotland. Canonized 1976 — the only post-Reformation Scottish saint.