Cromwell was born in Huntingdon, on 25th April 1599. He was the son of Robert Cromwell and Elizabeth Steward. He was not directly related to Thomas Cromwell, Henry VIII's chief minister, but a distant relation through marriage and the family still had lands that he had been given. Cromwell's grandfather had built a large house outside Huntingdon. Cromwell's father was a younger son who did not inherit much of the family fortune.