Fifty Regal Supervan IIIs entered service with the Royal Mail on a trial basis in 1970, but the model was not selected as the service’s eventual successor to the Morris Minor.

In 1935 Tom Williams made a three-wheeled van - essentially a motorcycle encased within a box body - in his garden in Tamworth and founded the Reliant Engineering Company. Vehicle production began with vans and manufacturing continued to be based in and around Tamworth until 1998.

Passenger cars were added to the line up in 1952 - the first Regal. Initially using aluminium panels over a wooden body frame, Regal bodies were made from glass fibre reinforced plastic from 1955. For the average car buyer, the Regal offered advantages in low running costs, good economy and lower vehicle tax, as well being able to be driven by people with a motorcycle licence.

When the Morris Minor van was reaching the last days of its production, the Post Office investigated a number of models as a replacement for its fleet of delivery vans. The Supervan III was trialled due to its cost effectiveness but they were not popular and the Post Office chose to temporarily use Minivans instead.