George de Grey, 3rd Baron Walsingham  George de Grey, 3rd Baron Walsingham (11 June 1776 – 26 April 1831), of Merton Hall, Norfolk, was a British peer and Army officer. He was the eldest son of Thomas de Grey, 2nd Baron Walsingham, and his wife Augusta Georgina Elizabeth Irby. He succeeded his father in 1818. He joined the British Army in 1794 as a Cornet in the Royal Dragoons, becoming a Lieutenant and then Captain in 25th Light Dragoons in 1794. He was promoted Major in 1795 and was present at the surrender of the Dutch fleet in Saldanha Bay, Cape Colony, in 1796. He served in India from 1796 to 1800, taking part in the Battle of Mallavelly and the capture of Seringapatam in 1799, after which he was made Lieutenant-Colonel of the Royal Dragoons. He served as assistant Adjutant General, Home District, from 1803 to 1805, was made a Colonel in the Army and ADC to the King in 1808. He took command of his regiment in the Peninsula War from 1809 to 1812 and command of a Cavalry Brigade in 1810, fighting at the Battles of Busaco (1810), Albuera and Usagre (1811). He was promoted Major General in 1811 and Lieutenant General in 1821. He was appointed Comptroller of the First Fruits and Tenths. He died with his wife in a fire at his house in Upper Harley Street in 1831 and was buried at Merton. He had married in 1804 Matilda Methuen, the daughter of Paul Cobb Methuen MP, of Corsham, Wiltshire, but left no children. He was succeeded in the barony and to Merton Hall by his brother Thomas de Grey, 4th Baron Walsingham, the Archdeacon of Surrey.