He was a "sincere, plain, direct man, not crafty nor involved", whose "delight was music and poetry and his exercise war" who co-authored[2] a treatise on hare coursing.

[5] Parr took part in suppressing the rising in the North of England in 1537, when he attracted the favourable notice of Thomas Howard, 3rd Duke of Norfolk (uncle of both Queen Anne Boleyn and Queen Katherine Howard), encouraging his uncle Sir William Parr (c.1483–1547) of Horton, Northamptonshire, to obtain a place for him as a courtier in the King's Privy Chamber.

Parr served as Lord Lieutenant in 1549 of five of the eastern counties (Cambridgeshire, Huntingdonshire, Bedfordshire, Northamptonshire and Norfolk), of Surrey in 1551, of Berkshire and Oxfordshire in 1552 and of Hertfordshire and Buckinghamshire in 1553.

He served as Lord Great Chamberlain from 1550 to 1553, in which role in 1551 he welcomed Mary of Guise, Regent of Scotland, to Hampton Court Palace on behalf of the King.

[10] Parr, and especially his wife, were leaders in the attempt to put the Protestant Lady Jane Grey (daughter-in-law of Northumberland) on the throne after Edward's death (as that king had desired) in place of the other contender his half-sister the Roman Catholic Queen Mary.