Accordion and Recorder Storm Concert Hall

The "two unlikely instruments" will rock the Quad City Symphony Orchestra in Rock Island, Ill., according to The Des Moines Register. (Wonder if Rick Neilsen will make the show?)

And that's all well and good. But these paragraphs pique my interest:

Although the accordion has all the flashy range of a violin or trumpet, few classical composers have written pieces to show off its range, partly because it developed later than more popular instruments.

Adapted from a Chinese reed instrument called a cheng, the accordion wasn't introduced in Europe until the late 1700s. Patents for the instrument didn't emerge until the 1820s in Austria and Germany.

I keep hearing conflicting stories about the genesis of the accordion -- I've even heard that the piano accordion was invented in San Francisco, which sounds bogus to me. I mean, this city "invented" sourdough bread by letting some yeast go bad, right?

Can anybody shed light on the undeniably real history of the accordion?