What's the origin of "to string somebody along"?

Solution 1:

According to Green’s Dictionary of Slang the original idea is probably that of being dragged along on a string:

string (along) v.:

1. in senses of persuasion [the image of dragging someone along on the end of a string].

• (a) to fool, to deceive someone, esp. over a drawn-out period of time; to tease; thus stringing n.

Early usage examples:

• 1812 [UK] Vaux Vocab. of the Flash Lang. in McLachlan (1964) 251: To banter or jest with a man by amusing him with false assurances or professions, is also termed stringing him, or getting him in tow.

• 1830 [UK] W.T. Moncrieff Heart of London II i: A very soft move his coming here, considering how he’s been strung by our Nottingham merchant here.