The Auster J/1 Autocrat was a 1940s British single-engined three-seat high-wing touring monoplane built by Auster Aircraft Limited at Rearsby, Leicestershire.
As the end of the Second World War approached the designers at Taylorcraft decided to develop a tourer version of the robust and reliable Taylorcraft Auster Model J AOP.V observation aircraft series. An Auster 5, registered G-AGOH, was modified to take a 100 hp (75 kW) Blackburn Cirrus II engine for trials. At the same time a prototype aircraft was built designated the Taylorcraft Auster V Series J/1 Autocrat. The long name was not used as the company changed name to Auster Aircraft Limited and the aircraft became known as the Auster J/1 Autocrat.
The designation J/1 derived from the progenitor Model J, which was the Auster AOP.V.
The first production aircraft, registered G-AGTO, was delivered in December 1945. One of the more spectacular feats of the type was the first visit of a civilian aircraft to an aircraft carrier, HMS Illustrious in the English Channel in October 1946. The last Rearsby built J/1s were delivered in 1952.