The Heinkel was introduced in Germany, 1954 by Professor Ernst Heinkel. Heinkel had been to the Geneva Motor Show and had seen the ISO Isetta on display. Being the builder of the first rocket powered aircraft Heinkel's aircraft company was experiencing financial problems as after World War 2 the need for aircraft dramatically dropped. Heinkel was at the time already producing two-stroke engines for SAAB and in 1952 also produced a scooter. Inspired by the Isetta Ernst Heinkel set about building his own vehicle. He believed the Isetta was too heavy a vehicle and so did not apply to ISO for a patent as his vehicle would be completely different internally though externally it would look similar. As Heinkel was building his vehicle, BMW had taken out the ISO patent for the Isetta and had started to manufacture it themselves. In 1955 BMW discovered that the Heinkel looked like their Isetta and so a meeting was arranged for Ernst Heinkel to meet the head of BMW; Kurt Donath. During the meeting Heinkel stated that his vehicle was in no way similar to the Isetta and that it would not start full production until 1956. Grasping the sales advantage BMW started production of the Isetta one month after the meeting in April 1955. Powered by a 204cc four-stroke engine the Heinkel went into mass production as planned in 1956 and was some 100kg lighter than the Isetta.
The Heinkel featured an opening front that led to a bench type seat and unlike the Isetta the steering column was static when the door was opened. Despite this however the Heinkel is said to be a lot roomier inside than the Isetta.
The last German built Heinkel was made in June 1958 (the year that Ernst Heinkel died) and the Irish Government started negotiations for a take over bid. The bid was successful and production of the Heinkel was moved from Speyer to Dundalk in Ireland. In 1963 Trojan of Croydon took over the plant and production was switched to Croydon (UK) where they continued to make the Heinkel under the new name of the Trojan, the engines of which were still made in Germany. With the Trojan later being modified to be right hand drive for the UK market production continued until 1965 when the competition against the Austin Mini put great strains on sales. Although Trojan ceased in 1965, Heinkel continued to make engines until 1967 when Heinkel then also ceased production