By an ironic sort of providence, Thomas Mifflin served as George Washington's first aide-de-camp at the beginning of the Revolutionary War, and, when the war was over, he was the man, as President of the Continental Congress, who accepted Washington's resignation of his commission.
Most of Mifflin's significant contributions occurred in his earlier years — in the First and Second Continental Congresses he was firm in his stand for independence and for fighting for it, and he helped obtain both men and supplies for Washington's army in the early critical period. In 1784, as of the President of the Continental Congress, he signed the treaty with Great Britain which ended the war. Although a delegate to the Constitutional Convention, he did not make a significant contribution — beyond signing the document.