Green’s Dictionary of Slang

bel-shangle n.

a fool.

1847–81		(ref. to 1600) Halliwell Dict. Archaic and Provincial Words I 163/1: bel-shangles: A cant term used by Kemp, in his Nine Daies Wonder, 1600, where he mentions himself as ‘head-master of Morrice-dauncers, high head-borough of heighs, and onely tricker of your trill-lilles, and best bel-shangles betweene Sion and mount Surrey.’.
1937–84		Partridge DSUE (1984) 67/1: late 16C–early 17C.