R. B. Longridge and Company was established in 1785 at Bedlington, Northumberland, England. Its proprietor was Michael Longridge who also managed Robert Stephenson's works during the latter's absence abroad. He was also proprietor of the Bedlington Ironworks which pioneered the rolling of long malleable iron rails.
The first locomotive was an 0-6-0 called Michael Longridge for the Stanhope and Tyne Railway. This was followed by a number of 2-2-2 locomotives for several European railways, including Arend the first locomotive to work on a public railway in the Netherlands. Some broad gauge singles were also built in 1841 for Daniel Gooch of the Great Western Railway.
Business increased in 1846 with about sixty engines for the London and Birmingham Railway, the Midland Railway and the London, Brighton and South Coast Railway. While the export trade experienced a lull, orders continued to be fulfilled for the home railways, including ten 4-2-0 Crampton locomotives for the Great Northern Railway, which were later converted to 2-2-2s by Archibald Sturrock.
By the time the works closed in 1853 it had produced some two hundred engines.