He entered the Benedictine order as a boy, studied at the College de Sorbonne in Paris, and became successively prior of St. Baudil, abbot of Fécamp, bishop of Arras, chancellor of France, archbishop of Sens and archbishop of Rouen. He was made cardinal-priest of Santi Nereo e Achilleo and administrator of the bishopric of Avignon by Benedict XII in 1338, and four years later succeeded him as pope.
Like his immediate predecessors, he was devoted to France, and he demonstrated his French sympathies by refusing a solemn invitation to return to Rome from the city's people, as well as from the poet Petrarch. He however threw a sop to the Romans by reducing the Jubilee term from one hundred years to fifty. He also purchased the sovereignty of Avignon from Queen Joan I of Naples, for 80,000 crowns. The money was never paid, but Clement VI may have deemed that he gave the queen a full equivalent by absolving her from the murder of her husband.
Clement VI issued the Bull Unigenitus, January 27, 1343, in order to justify the power of the pope and the use of indulgences. This document was also used in the defence of indulgences after Martin Luther pinned his 95 Theses to a church in Wittenburg on October 31, 1517.
Clement VI reigned during the Black Death. This pandemic swept through Europe (as well as Asia and the Middle East) between 1347–1350, and is believed to have killed between a third and two thirds of Europe's population. During the plague, he sought the insight of astronomers for explanation. Jehan de Murs was among the team "of three who drew up a treatise explaining the plague of 1348 by the conjunction of Saturn, Jupiter, and Mars in 1341" (Tomasello, 15). Clement VI's physicians advised him that surrounding himself with torches would block the plague. However, he soon became skeptical of this recommendation and stayed in Avignon supervising sick care, burials, and the pastoral care of the dying (Duffy, 167). He never contracted the disease. One of his physicians, Gui de Chauliac, later wrote the Chirurgia magna.
Popular opinion blamed the Jews for the plague, and pogroms erupted throughout Europe. Clement issued two papal bulls in 1348 (one on July 6) which condemned the violence and said those who blamed the plague on the Jews had been "seduced by that liar, the Devil." He urged clergy to take action to protect Jews, but the orders appeared to have little effect, and the destruction of whole Jewish communities continued until 1349.
Clement continued the struggle of his predecessors with the Emperor Louis IV. He excommunicated him after protracted negotiations on April 13, 1346, and directed the election of Charles IV, who received general recognition after the death of Louis in October 1347, putting an end to the schism which had long divided Germany. Clement proclaimed a crusade in 1343, but nothing was accomplished beyond a naval attack on Smyrna (29 October 1344).
The other chief incidents of his pontificate were his disputes with Edward III of England on account of the latter's encroachments on ecclesiastical jurisdiction, as well as with the kings of Castile and Aragon; his fruitless negotiations for reunion with the Armenians and with the Byzantine emperor, John VI Kantakouzenos; and the commencement of Cola di Rienzo's agitation at Rome. He had appointed Cola to a civil position at Rome, and, although at first approving the establishment of the tribunate, he later sent a legate who excommunicated him and, with the help of the aristocratic faction, drove him from the city in December 1347. Clement also excommunicated Casimir III of Poland and made Prague an archbishopric in 1344.
Clement VI died in December 1352, leaving the reputation of "a fine gentleman, a prince munificent to profusion, a patron of the arts and learning, but no saint" (Gregorovius; see also Gibbon, chap. 66).
Unlike the Cistercian Benedict XII, Clement VI was devoted to lavish living, and the treasury which he inherited made that lifestyle possible. He claimed to have "lived as a sinner among sinners", in his own words. During his pontificate, he added a new chapel to the Papal Palace and dedicated it to St. Peter. He commissioned the artist Matteo Giovanetti de Viterbo to paint common hunting and fishing scenes on the walls of the existing papal chapels, and purchased enormous tapestries to decorate the stone walls. In order to bring good music to the celebrations, he recruited musicians from northern France, especially from Liège and of the Ars Nova style. He liked music so much that he kept composers and theorists close to him throughout his entire pontificate, Philippe de Vitry being among the more famous. The first two payments he made after his coronation were to musicians (Tomasello, 12-20).