How about one chord songs?

Paddy and the Whale
or Ground Hog

Several other classics are almost one chord songs (on a 1 chord) frequently switching to a fifth (5 chord) before the final measure and back to the one chord to conclude:

Turkish Revery - Key of Eb = CM.....................G,Cm.

Lily Munro - = Cm................Gm,Cm

Barb'ry Allen = Eb..............Bb7,Eb

The Swap Song = G.................D7,G

Hullabaloo Belay = Dm................Am,Dm

Jennie Jenkins = F........................C7,F

Cotton Eye Joe = G.......D7....G

or...almost, almost,almost one chord songs Joe Clark = Eb...........Bb7,Eb......Bb7,Eb.......Bb7,Eb

Leatherwing Bat = Em.............Am.Em.......Am,Em