The Riley family had been long established as master weavers, but loss of trade to Germany and Austria caused William Riley to acquire the Bonnick Cycle Company in 1890. William's five sons experimented with engines in their off-duty time, as their father did not approve. Their first powered vehicle was a tricycle in 1899. In 1902 Victor, Percy (designer) and Allan started The Riley Engine Company to build engines for their fathers' products and others (including Singer). They patented the mechanically operated inlet valve.

In 1902 the Riley Cycle Company produced their first four-wheeled car. 1907 saw the announcement of the first detachable road wheel, designed by Percy. These wheels became an important part of the company's business as demand became worldwide, 183 manufacturers paid to use the patent rights. The company nearly decided to concentrate on wheel production but William persuaded them otherwise and in 1912 a separate company was formed to manufacture wheels, this was eventually sold.

Bicycles were discontinued in 1911 and a new Light Car was introduced in 1919, designed by Harry Rush. (Their first car not designed by a member of the Riley family). This car was the first to carry the diamond Riley badge.

Lord Nuffield bought Riley privately when they went into receivership, and later sold it to his own Morris Empire.

1.5 liter (1936)

Throughout the 1930's Riley achieved much sporting success and became a make to be reckoned with. JG Parry Thomas built and raced the Brookland Riley Nine until his death in 1927, when the work was continued by Reid Railton who was then working with Thomson & Taylor.

Pathfinder (1953)

The Pathfinder of 1953 to 1957 was the last Riley to use a Riley engine.

The 1957 1.5 litre model had a body shell that was intended to be the replacement for the Morris Minor 1000, but as the Minor was selling well this did not happen. The Riley 1.5 used the Minor's base frame (The Wolseley version was similarly constructed) with a twin carburettor version of the BMC B-Series engine. This was almost the MGA tune and gave the car a lively performance.

4/72 (1961)

In 1961 a Riley version of the Mini appeared. It was named the Elf and had a better standard of internal trim than the standard car, but the most noticeable feature being the extended boot.

The last use of the Riley name was the Kestrel, a re-badging of BMC's 1100 and 1300 models, until British Leyland stopped using the name Riley in 1969.