He wrote to her on 10 June 1554 describing a skirmish in which his cousin George Drummond of Ledcrieff was killed by the lairds of Ardblair, Drumlochie, and Gormok, his followers.
Subsequently, however, he joined the league against the Earl of Huntly, whom with Murray and Morton he defeated at Corrichie in October 1562, and he supported the projected marriage of Elizabeth I with Arran.
He was described the same year by the French ambassador as "très grand catholique hardi et vaillant et remuant, comme l'on dict, mais de nul".
[3] After the murder of David Rizzio in 1567, he joined the Protestant lords against Mary, appeared as one of the leaders against her at Carberry Hill, and afterwards approved of her imprisonment at Lochleven Castle.
In March 1570 he formed with other lords the joint letter to Elizabeth asking for the queen's intercession and supporting Mary's claims, and was present at the convention held at Linlithgow in April in opposition to the assembly of the king's party at Edinburgh.
[4] In 1574 he was proceeded against as a Roman Catholic and threatened with excommunication, subsequently holding a conference with the ministers and being allowed till midsummer to overcome his scruples.
Atholl and Argyll, who were now corresponding with Spain in hopes of assistance from that quarter, then advanced to Stirling with a large force, when a compromise was arranged, the three earls being all included in the government.