Formed in 1903 by the amalgamation of Glasgow's three major locomotive building concerns; Neilson Reid and Co.; Hyde Park Works, Dubs & Co.; Queen's Park Works, and Sharp Stewart & Co.; Atlas Works. North British became the largest locomotive builder in Europe. Each factory retained its own distinctive works plate, Hyde Park Works being circular, Queen's Park diamond and Atlas oval.

North British built locomotives for many major railways of the world as well as the smaller industrial concerns. Among their better known products were the first fifty of the Royal Scot class for the LMS, and during World War Two the Riddles designed Austerity 2-8-0s and 2-10-0s. The African and Asian continents were by far the best customers and many Garratt and Mallet types were exported to these countries.

North British is another example of a firm whose downfall was due to the diesel locomotive. The company made a bad choice of hydraulic transmission / diesel engine combination, and thus found it could not compete with competition from America and Japan in its traditional markets. Neither did it have the capital to re-equip its plants to produce better designs. So in 1963 Andrew Barclay took over NBL's diesel business, the company carrying on its other work before being wound up a few years later. In turn Andrew Barclay have now become part of the Hunslet Group. Of NBL's more successful diesel designs, perhaps the batch of Warship class built for British Railways, Western Region, will be best remembered.

Examples at Quainton

Examples Previously at Quainton