The DS420 appeared in 1968 after Jaguar merged with the British Motor Corporation in 1966. Both companies then had an ageing limousine, the Daimler Majestic Major and the Vanden Plas Princess 4 litre, and Jaguar chose the Daimler name for the single replacement.
The car used an extended floorpan from the Jaguar 420G and the 4.2-litre Jaguar six-cylinder engine, which makes 245 PS. An automatic gearbox was standard. It was built at Vanden Plas in Kingsbury, London. When that plant closed in 1979, production moved to Jaguar in Coventry, where final assembly and trim were done at the Browns Lane limousine shop from 1980.
The DS420 was sold as a Limousine and as a Landaulette until 1992. Funeral firms, car hire companies and official users were typical customers.