In 1774, Frederick was returned as Member of Parliament for Newport, Cornwall in the interest of Humphry Morice. By 1780, Morice had sold his borough and Frederick was not returned in 1780. He sought another seat and was returned for Christchurch at a by-election in 1781. On the death of his father on 9 April 1783, he succeeded to the Baronetcy. He was re-elected for Christchurch in 1784. In 1790, he was elected MP for his home county Surrey and held the seat until 1807.[2][3]
He served as lieutenant-colonel of the 1st Supplementary Surrey Militia (later 2nd Royal Surrey Militia from its first raising on 2 January 1797 until his resignation on 26 October 1804. His son Richard was also an officer in the regiment and commanded it in Ireland from 1811–13.[4]
Family
Walton-on-Thames, St Mary's Churchyard
He married Mary Garth, daughter of Richard Garth of Morden, Surrey, on 15 October 1778, and they had six sons and four daughters, including:[2]
Thomas Nathan Frederick, born on 11 July 1783, died in 1818
Charlotte Frederick, married Rev R.A. St Leger of Starcross, Devon, and died in 1858
Mary Frederick, married James Chamness Fisher of Twickenham and died on 2 April 1823
Frances Frederick, married Henry Fellowes, 2nd son of Robert Fellowes of Shotesham, Norfolk, and died on 28 April 1874
Sir John Frederick died on 16 January 1825[2] and was buried at Walton-on-Thames where there is an unusual pyramid-shaped monument to him and his wife.
