The Brotherhood was designed by Percy Richardson, formerly of Daimler and made by a subsidiary of the large engineering firm, Peter Brotherhood, which had been formed in 1867. Their main factory was on the South Bank of the Thames near Westminster Bridge, and it is likely that the car’s components were made there and assembled at West Norwood. The directors were Stanley Brotherhood and Jonathan Crocker, and a major shareholder was the Yorkshire landowner and coal magnate Earl Fitzwilliam. The car was a high-quality product with 12/16hp pair-cast 4-cylinder engine and double chain drive. It was succeeded in 1905 by a larger car with 20hp engine and only two pedals, the functions of brake and clutch being combined in one. The accelerator worked in an arc rather than an up and down movement.
Not long after production of the 20hp started, the parent company sold their London premises, which became the site of County Hall, and moved to Peterborough where they still exist today, now under American ownership. They could not obtain planning permission for a car factory at Peterborough, but Earl Fitzwilliam suggested a move to Sheffield. ‘We make the steel in Sheffield; why are the cars made in London, Birmingham and Coventry? he asked. He spent £10,990 on the erection of a factory at Tinsley on the eastern outskirts of Sheffield, and it was completed in July 1906. Although the Brotherhoods no longer had any connection with the cars, the company continued to trade under the Brotherhood-Crocker name, with Percy Richardson still in charge of design, up to late 1907. In November of that year a new car was announced under the name Sheffield Simplex; it bore little resemblance to the Brotherhood, though Richardson remained as chief designer.