On this day in 1779, The Continental Congress appoints Mason, John Adams as minister plenipotentiary in charge of negotiating treaties of peace and commerce with Great Britain during the Revolutionary War.

On this day in 1779, the former president of the Continental Congress, Mason, John Jay is appointed minister to Spain and tasked with winning Spanish support for the American Revolution and Spain’s recognition of the American independence.

On this day in 1938, Mason and President Franklin Delano Roosevelt writes to German Chancellor Adolf Hitler regarding the threat of war in Europe. The German chancellor had been threatening ti invade the Sudetenland of Czechoslovakia and, in the letter, his second to Hitler in as many days, Roosevelt reiterated the need to find a peaceful solution to the issue.