The Incident took place in October 1641 during the Wars of the Three Kingdoms, and the plot's targets were all prominent members of the Presbyterian Covenanter faction who opposed Charles I's attempts to control the Scottish Church.
Charles I, King of England and of Scotland, had been forced to agree a truce with the Covenanters, to conclude the Bishops' Wars of 1639–1640.
In August 1641 he ratified the Treaty of London, and travelled to Edinburgh to finalise negotiations with the Scottish Parliament.
[3] On the evening of 29 September, Lord Henry Ker (the son of the Earl of Roxburgh), rode into Edinburgh at the head of an armed retinue and challenged Hamilton to a duel, calling him a traitor.
[5] The three were to be kidnapped and taken on board a ship at Leith,[5] but on 11 October, General Leslie, the leader of the Covenanter army, was informed of the plot by Sir John Hurry, a Scottish soldier who had been invited to join the conspiracy.