Edmund Crouchback, 1st Earl of Lancaster (January 16, 1245 – June 5, 1296) was the second surviving son of Eleanor of Provence and King Henry III of England.

Crouchback was born in London, England. In 1253 he was invested by the Pope in the Kingdom of Sicily and Apulia. At about this time he was also made Earl of Chester. These were of little value as the real King of Sicily was still living and the Earldom of Chester was transferred to his elder brother Edward. Edmund soon obtained, however, important possessions and dignities, for soon after the forfeiture of Simon de Montfort in 1265, Edmund received the Earldom of Leicester and of Lancaster and also the honour of the Stewardship of England and the lands of Nicolas de Segrave .

He was married twice, first to Aveline de Forz, Countess of Albemarle, in 1269, and then in Paris, France on February 3, 1276, to Blanche of Artois. That same year he became the Count of Champagne and Brie in France. With Blanche he had four children:

• Thomas Plantagenet, Second Earl of Lancaster (b. 1276)
• Henry Plantagenet, 3rd Earl of Leicester (b. 1281)
• John Plantagenet, Lord of Beaufort, (b. BEF 1286)
• Mary Plantagenet

He died on June 5, 1296 in Bayonne, and was interred on July 15, 1296 at Westminster Abbey, London, England.

|- style="text-align: center;" | width="30%" |Preceded by:
The Earl of Leicester | width="40%" style="text-align: center;" |Lord High Steward
1265–1296 | width="30%" |Succeeded by:
The Earl of Leicester and Lancaster