king of the Romans from 1256 to 1271, aspirant to the crown of the Holy Roman Empire.

He was the second son of King John of England and was created Earl of Cornwall (May 30, 1227). Between 1227 and 1238 he frequently opposed his brother, King Henry III by joining the barons in several crises but never proceeding to rebellion and always making Henry pay heavily for reconciliation. He took the cross (1236) and led a small English force to the Holy Land (June 1240–January 1242), refortifying Ascalon and negotiating an advantageous treaty. During Henry III's disastrous Poitevin campaign in France (1242), Richard's prompt retreat at Saintes and his persuasive diplomacy at Taillebourg saved Henry from capture. While acting regent of England during Henry's Gascon visit (1253–54), Richard summoned knights to represent the shires at the critical Easter Parliament of 1254. Reputedly the richest magnate in England, he refused Pope Innocent IV's offer of the Sicilian crown (1252–53) but accepted imperial candidature (1256), purchased four of the seven electoral votes, was elected king of the Romans and crowned at Aachen (Aix-la-Chapelle; May 17, 1257). By lavish bribery he gained recognition throughout the Rhineland, returning home in January 1259.

He helped Henry to overthrow the Provisions of Oxford, but from June to October 1260 he again visited Germany, then discovering the impossibility of his hopes of the imperial crown.

He helped Henry invaluably against the rebel barons (1263–64) but was captured at Lewes (May 14, 1264) and imprisoned at Wallingford and then at Kenilworth until the overthrow of Simon de Montfort at Evesham (Aug. 4, 1265). He then worked ceaselessly to obtain the relatively moderate settlement of the Dictum of Kenilworth (Oct. 31, 1266). His fourth and last visit to Germany (August 1268–August 1269) is notable only for his third marriage, to Beatrice of Falkenburg.