Major-General Robert Overton c. 1609 to 1678, was a member of the landed gentry from Yorkshire, who fought for Parliament during the Wars of the Three Kingdoms, and reached the rank of Major General in 1652. A committed republican and religious Independent who sympathised with the Fifth Monarchists, like others with similar views he opposed the establishment of The Protectorate, and was held in the Tower of London from 1655 to 1659.

The Fifth Monarchists, or Fifth Monarchy Men, were a Protestant sect which advocated Millennialist views, active during the 1649 to 1660 Commonwealth of England. Named after a prophecy in the Book of Daniel that Four Monarchies would precede the Fifth or establishment of the Kingdom of God on earth, the group was one of a number of Nonconformist sects that emerged during the Wars of the Three Kingdoms. Perhaps its best known adherent was Major-General Thomas Harrison, executed in October 1660 as a regicide, while Oliver Cromwell was a sympathiser until 1653.