George Guelph

http://www.thebeerbarrel.net/showthread.php?7915-Thomas-Jefferson-on-George-Guelph-(the-Third)

Thomas Jefferson was of the 'Old Whig' party, as were all the Founding Fathers. That is, they supported the Glorious Revolution of 1688 (the defeat of King James II at the Battle of the Boyne), but opposed the 'New Whig' Oligarchy ruled over by Pitt, whom they claim perverted the aforesaid Revolution. Consequently, they supported the Stuart claims over the House of Hanover, though Adams saw himself as the second coming of Oliver Cromwell [a Republican], and Jefferson supported the anti-Stuart politics of the lawyer Edward Coke.

The Hanoverians were well-known to be part of the Black Guelph dynasty (which included Russian Romanovs and Austrian Hapsburgs, eventually, as well), that ruled Europe at the time. Making political hay of this was a typical American response to this dynasty in Europe, for Jefferson's era.