Originally founded in 1867 at Manchester by brothers Francis & William Crossley the Crossley Brothers company made various engines & pumps etc. and machinery for other manufacturing enterprises. Crossley Motors began as a separate enterprise in 1906 and manufactured a variety of vehicles. It was taken over by AEC in 1948 forming a small part of the new ACV Group. Soon after this acquisition Crossley mostly "badge engineered" AEC products (in the same way as its new sibling company Maudslay) until it was closed in 1958.
Though designed at Park Royal the original AEC Bridgemaster was not built there; the final design & build of the prototype took place at Crossley Motors instead. And in this form the Bridgemaster made its debut at the 1956 commercial motor show looking, in my opinion, like an amalgamation of Regent style front ending and Routemaster rear.
Here is the advertisement flyer for the prototype Bridgemaster from Crossley dated August 1st 1956 (Or Click Here for the full advertisement text).
(see the Bridgemaster page)
is the first of the only batch of thirty-nine Regal IVs (Fleet Nos. 290-328) with
Crossley built bodywork that were all delivered in 1952 (except Fleet Nos. 312 &
325-8 that were delivered in early '53) to the Christchurch Transport Board in New Zealand.
(See here for the story of these AEC Regal IVs)
Crossley were also involved in the building of Railcars for British Railways (see here).