Henry of Grosmont , 1st Duke of Lancaster , 4th Earl of Leicester and Lancaster , KG ( c . 1310 – 23 March 1361 ) , also Earl of Derby , was a member of the English nobility in the 14th century , and a prominent English diplomat , politician , and soldier . The son and heir of Henry , 3rd Earl of Lancaster , and Maud Chaworth , he became one of Edward III 's most trusted captains in the early phases of the Hundred Years ' War and distinguished himself with victory in the Battle of Auberoche . He was a founding member and the second Knight of the Order of the Garter in 1348 , and in 1351 was created duke . Grosmont was also the author of the book Livre de seyntz medicines , a highly personal devotional treatise . He is remembered as one of the founders and early patrons of Corpus Christi College , Cambridge , which was established by two of the guilds of the town in 1352 .