According to
David X. Cohen, many of the details seen in the crew's visit to the revolutionary era were thoroughly researched and are historically accurate. The two-thirds dollar bill was a real denomination and modeled after revolutionary currency, the Continental Congress met in New York on the day the crew visits, and the opal that Professor Farnsworth steals from the queen is based on an actual opal found in the Crown Jewels. Cohen admits that one historical inaccuracy intentionally overlooked was
Benjamin Franklin's presence in America on that day. In actuality, Franklin would have been crossing the Atlantic Ocean on his way back from Europe.