John Pratt, 4th Marquess Camden

John Charles Pratt, 4th Marquess Camden GCVO TD DL JP (9 February 1872 – 15 December 1943), briefly styled Earl of Brecknock in 1872, was a British peer.

Camden was born at Eaton Square, London, the third but only surviving son of John Pratt, 3rd Marquess Camden, by Lady Clementina Augusta, daughter of George Spencer-Churchill, 6th Duke of Marlborough. He was a first cousin of Lord Randolph Churchill on his mother's side. He succeeded to the marquessate at the age of only two months on the early death of his father, and was subsequently educated at Eton and Trinity College, Cambridge.

In 1905 Camden was appointed Lord-Lieutenant of Kent, a position he held until his death. He fought in the First World War as a Major in the West Kent Yeomanry Cavalry, where he was awarded the Territorial Decoration. He was also a Deputy Lieutenant of Sussex between 1894 and 1922 as well as a Justice of the Peace for the county. He was appointed a Knight Grand Cross of the Royal Victorian Order in 1933. From 1942 to 1943 he was Commodore of the prestigious Royal Yacht Squadron.

Lord Camden married Lady Joan Marion, daughter of Henry Nevill, 3rd Marquess of Abergavenny, in 1898. They had two sons and two daughters. He died in December 1943, aged 71, and was succeeded in the marquessate by his eldest son, John. The Marchioness Camden died in July 1952, aged 74.