American Treason law’s Origins

Bradley Chapin states that American treason law originated as “a product of the
[American] nation” and developed “from the experience of the Continental army between June 1775 and June 1776.”43 At the time, military and civilian disloyalty threatened the Continental army. In order to combat military disloyalty, the Continental Congress established the Articles of War on June 30, 1775, to provide rules and regulations on proper military conduct in order to prevent mutiny and sedition.

What was the Continental Congress? Check out the video below to learn more: 

On the other hand, American loyalists in the civilian population
posed a major threat to the Patriot cause as they could also serve as agents of the British crown. As agents, American loyalists could start violent uprisings and share intelligence on the state of the Continental army with British officials. Additionally, the revolutionaries had difficulties taking stern measures against dissidents “as long as the colonies technically remained in allegiance to the king. Social pressure and mob action might effectively control the timid and the uncertain, but more drastic powers were needed to be dealt with.”44 These difficulties were especially severe when King George III issued a proclamation in the autumn of 1775 calling for “his officers and loyal subjects in America to aid in suppressing rebellion and sedition.”45

The following video details the words writtend in King George III's Proclamation of 1775. 

King George III made his own case for loyalty and treason in August 1775. To maintain their allegiance to their king, loyalists in Philadelphia transmitted intelligence to the British in reference to the status of the Continental army.
46 This alarmed Pennsylvania’s Revolutionary leaders who believed the King’s proclamation served as an open invitation for the British to invade Pennsylvania. This then caused the Continental Congress to “immediately [recommend]
that the provincial assemblies and committees of safety arrest and secure all persons ‘whose going at large may endanger the safety of the colony, or the liberties of America.’”47

King George III as a young man in 1755. 

American Treason law’s Origins