Jigsaw puzzles weren't a single "eureka" invention — they evolved from educational tools → commercial entertainment → mass-market staple over 150 years.
John Spilsbury (London engraver/mapmaker) mounted maps on mahogany, cut along county/country borders with a marquetry saw. Sold to wealthy boarding schools to teach geography. Children reassembled Europe, England, the World. These were the first "jigsaws" — though the name came later.
Not one inventor — a cultural innovation shaped by tools, economics, and the human love of fitting pieces together.