In Britain, brass bands weren't so much an invention as a development. They came about partly as a way providing a cultural activity for the employees of mills and mines (also a way of controlling the rapidly growing industrial workforce). They were enabled by the mass production and availability of quality instruments.
Trevor Herbert is a leading authority on the history of the brass band, and there's an article here that you might find interesting:
http://fds.oup.com/www.oup.co.uk/pdf/0-19-8166 98-2.pdf