On 19 August 1423 "George, Earl of March" and his brother Sir Patrick de Dunbar of
Beil were named as part of the embassy sent to negotiate the liberation of King
James I of Scotland who had long been a captive in England. On 28 March 1424, the Earl of March was one of the Conservators of the seven-year truce with England, and met James I and
his consort at
Durham upon their return to Scotland. He was also present at their Coronation in
Scone on 21 May 1424, when he was
knighted. However, the following year the earls of Dunbar and Douglas, with the Duke of Albany, and twenty other feudal barons, were suddenly arrested and confined by order of parliament after accusations of corruption in Scottish affairs during James's absence. Albany and his sons, with his father-in-law the
Earl of Lennox, were beheaded, but the Earl of Dunbar and most of the other barons were set at liberty, their guilt being less apparent. In 1427 the earls of Dunbar and
Douglas obtained, in London, a truce from King
Henry VI of England for two years, which Sir
Robert Umfraville, governor of
Berwick-upon-Tweed had refused. George was next employed in negotiating more temporary truces with England in June 1429 and the following January; and officiated as sponsor for King
James II of Scotland at
Holyroodhouse in October 1430. ==Conspiracy and downfall==