In 1862, the West Midland Railway ordered six express locomotives with a 2-4-0 wheel arrangement from Beyer, Peacock & Co. for their topographically more demanding routes. They featured straight outer frames and a polished brass steam dome. At the same time, six locomotives with the wheel arrangement 2-2-2 were built, which had the same boiler. As early as 1863, the WMR was merged into the GWR, with the locomotives being given the numbers 196 to 201.

No. 201 after rebuild to a tank locomotive

Locomotive Magazine, October 1915

In the years 1879 to 1881 three of the locomotives were converted into tank locomotives, giving them a slightly longer wheelbase, a new boiler and larger cylinders. Number 198 was also rebuilt in 1884 with the same boiler and cylinders, but remained a tender locomotive. 

No. 197 after the renewed rebuild to a tender locomotive

Locomotive Magazine, October 1915

Since the conversion of the 198 obviously proved to be the best, the three locomotives that had already been converted into tank locomotives and the remaining two were also converted in the same way between 1885 and 1887. The six sister machines with the 2-2-2 wheel arrangement had already been converted to the same form in 1882, with no part remaining the same apart from the front frame section. A final rebuild of all machines took place between 1893 and 1905, using a new boiler with a raised firebox top.