John Grey, 1st Earl of Tankerville

John Grey
Earl of Tankerville Lord of Powys, jure uxoris
Arms of Sir John Grey, 1st Earl of Tankerville, KG
Spouse(s)	Joan de Cherleton
Issue Henry Grey, 2nd Earl of Tankerville
Father	Sir Thomas Grey
Mother	Joan Mowbray
Born	after 1384
Died	22 March 1421

John Grey, 1st Earl of Tankerville, 6th Lord of Powys jure uxoris, KG (after 1384 – 22 March 1421) was an English peer who served with distinction in the Hundred Years' War between England and France under King Henry V.

The Grey family were descended from Sir Thomas Grey who during the reign of Edward III settled at Heton, Islandshire in Northumberland, and married an almost unknown gentlewoman named Agnes. He fought many wars for the English king on the Marches of the Scottish borders, dying about 12 March 1343/44. He was succeeded by his son, Sir Thomas Grey who married Margaret, daughter William de Pressene, of Presson, Northumberland.Pugh 1988, pp. 103, 187, 196 Sir Thomas fought in many battles, besieged castles, and wrote down the events in a celebrated historical account of the campaigns known as Scalacronica. He died shortly after its publication in about 22 October 1369, leaving the third Sir Thomas Grey, aged only ten years.

John Grey was the second son of Sir Thomas Grey (1359– 26 November 1400) of Berwick and Chillingham Castle. His wife was Joan Mowbray (d.1410), the daughter of John de Mowbray, 4th Baron Mowbray and 1st Duke of Norfolk by Elizabeth de Segrave, daughter and heiress of John de Segrave, 4th Baron Segrave. Through his mother, a granddaughter of Margaret, Duchess of Norfolk (d.1399), John Grey was a descendant of King Edward I.

Between 1408 and 1413 Henry V granted Grey three annuities, and on 8 August 1415 gave him the forfeited estates of his brother, Sir Thomas Grey, executed for his part in the Southampton Plot.

Grey fought at Agincourt in 1415. On 1 August 1417 Henry V launched his second invasion of Normandy, and in that year Grey was Captain of Mortagne in October 1417, and was with the King at the siege of Caen, where his valiant conduct caused the King to name him a Knight of the Garter. Henry V granted the castle and seigneurie of Tilly in Normandy in November 1417, recently forfeited by Sir William Harcourt, a supporter of the King's enemies.