Mainwaring is easily confused with his father, and here it is assumed that up until 1647, when the father died, references to ‘Edward Mainwaring’, without qualification, are to the latter. The Staffordshire Mainwarings were a junior branch of an ancient Cheshire family settled at Over Peover from the time of the Domesday Book. In 1546 Mainwaring’s great-grandfather, Edward Mainwaring, the sixth son of Sir John Mainwaring of Over Peover, married Anne Boughley, the heiress of Whitmore, a property situated four miles from Newcastle-under-Lyme. Mainwaring’s father was an important and well-connected figure in the region; Sir Richard Leveson* described him as his ‘well beloved friend’. He represented Newcastle-under-Lyme while studying at the Middle Temple in 1601 and subsequently served three times as mayor of the borough. He was also a prominent magistrate and an active Forced Loan commissioner.
Mainwaring himself grew up under the influence of the nonconformist John Ball, minister of Whitmore, who lived for many years with the Mainwarings. However, Mainwaring may have abandoned in adult life the Calvinism in which he was brought up. His ownership of the annotations on the Gospels and Old Testament of the Dutch Arminian Grotius points to this conclusion, as does the fact that in the 1650s Mainwaring befriended and protected William Higgins, a sequestered Anglican clergyman, who may have educated his eldest son.
The Edward Mainwaring elected for Newcastle-under-Lyme in 1625 was certainly the son rather than the father because the municipal records identify him as ‘the younger’.
In the 1630s Mainwaring became involved in his family’s longstanding feud with the Bowyers of Knypersley. In 1632 his brother John was presented to the rectory of Stoke-on-Trent by Roger Brereton, but the following year John Bowyer, cousin of Sir William Bowyer II*, was appointed to the same living by the Crown. The dispute that ensued led to the prosecution of John Mainwaring and Brereton for simony in the court of High Commission. John was exonerated but Brereton was not, and Mainwaring and his father were among Brereton’s compurgators.
Mainwaring and his father adhered to Parliament at the outbreak of the Civil War, and as a result Charles I purged the latter from the Staffordshire bench in the summer of 1642.
Mainwaring was buried at Whitmore on 23 Oct. 1674 and his will, dated 7 Jan. 1673, was proved at Lichfield on 24 July 1675.
