John Bastwick was born in Essex in 1593. When he finished his education at Emmanuel College, Cambridge, he took a medical degree at Padua.
Bastwick was released from prison in 1640 and during the Civil War served in the Parliamentary army. After the war Bastwick, a Presbyterian, advocated the persecution of other Puritan groups such as the Anabaptists, Quakers and Congregationalists. When his old friend, John Lilburne, complained, Bastwick arranged for him to be arrested.
John Bastwick died in 1654.