Nascom Microcomputers Ltd was established in 1977 as a subsidiary of the North American Semiconductor Company, a British company that distributed American semi-conductors and other electronics. The business sold the Nascom 1 and Nascom 2 kit computers, issued in 1977 and 1979 respectively. The Nascom 1 was created and designed by John Marshall and Chris Shelton. Unusually for the time, it was sold with a full keyboard and video display interface and so has a claim to be the first British-designed microcomputer. In order to keep costs down, the user had to hand solder hundreds of joints on the circuit board themselves. The magazine 'Wireless World' published a series of articles detailing the design process.

In 1978 Nascom established the International Nascom Microcomputer Club (later INMC80), as a forum to learn from its expert user community. The Club produced a newsletter for its members.

Nascom was sold to Lucas Logic, the computer applications subsidiary of the Lucas Group, in 1981 and was renamed Lucas Nascom.