Even more complicated than Snuffy indicates, since "When The King Enjoys His Own Again", as a Royalist song from the (English) Civil War, would very likely have been seen as a Jacobite and thus anti-Hanoverian song. (All right, there weren't too many Jacobites left by that time - but the king in question definitely isn't any George.)

But an excellent choice for Independence Day.

Pop Goes the Weasel was also the tune of the Cornwallis Country Dance.   Noone would know it, but it'd give a reason to play the tune, and it's a good one.