Markyate historically straddled the parishes of Flamstead in Hertfordshire, England, and Caddington, Studham and Houghton Regis (all in Bedfordshire) until 1897 when part of it became a separate parish in Hertfordshire and the remainder was absorbed into the respective Bedfordshire parishes.
Markyate first became a separate ecclesiastical parish, known as Markyate Street, in 1877. On 30 September 1897 the civil parish of Markyate was created from the Bedfordshire civil parish of Humbershoe (which in turn had been created in 1866 from part of the ancient parish of Studham) and the Bedfordshire and Hertfordshire portions of Caddington, Bedfordshire, Flamstead, Hertfordshire, an exclave of Houghton Regis, Bedfordshire known as Buckwood Stubbs, and an exclave of Whipsnade, Bedfordshire called Ballington Bottom which was in Hertfordshire.
Growth since the 1950s has been by infilling with new housing in the gap between the old A5 High Street and the new A5 Markyate by-pass.
For more information, see the EN Wikipedia article Markyate.