Thomas Mifflin was an American merchant, soldier, and politician from Pennsylvania, who is regarded as a Founding Father of the United States for his roles during and after the American Revolution. Mifflin signed the United States Constitution, was the first governor of Pennsylvania, serving from 1790 to 1799, and was also the state's last president, succeeding Benjamin Franklin in 1788. Mifflin's leadership in the Battle of Trenton and the Battle of Princeton led to a promotion to major general. In Congress, there was debate regarding whether a national army was more efficient or whether the individual states should maintain their own forces. As a result of this debate the Congressional Board of War was created, on which Mifflin served from 1777 to 1778. He then rejoined the army but took little active role, following criticism of his service as quartermaster general. He was accused of embezzlement and welcomed an inquiry; however, one never took place.

He resigned his commission, but Congress continued to ask his advice even after accepting his resignation. Prior to American independence, Mifflin was a member of the Pennsylvania Provincial Assembly. He served two terms in the Continental Congress, including seven months as that body's presiding officer. Mifflin's most important duty as president was to accept on behalf of Congress the resignation of General George Washington on December 23, 1783. On December 21, 1790, Mifflin became the last president of Pennsylvania and the first governor of the Commonwealth. He held the latter office until December 17, 1799, when he was succeeded by Thomas McKean. The Whiskey Rebellion and the 1793 Philadelphia yellow fever epidemic happened during his term in office. Fries Rebellion also started during his term. He then returned to the state legislature, where he served until his death the following month.