Thomas Cranmer played a significant and leading role during the English Reformation. He served as Archbishop of Canterbury during both the reigns of Henry VIII and Edward VI. Though he rose quite high in English government, his beginnings were humble.

His parents were landed but not noble. Thomas was a younger son, and so, according to the English tradition of primogeniture, he would receive little to nothing from his father's estate. Therefore, like many other English boys, he was trained for a career in the church. Little is known about his early education, but he did earn a Bachelor of Arts degree from Cambridge University, and went on to earn a Master's degree as well. However, and this is what puzzles scholars, he took an entire eight years just to complete the Bachelor's degree. Some scholars believe this indicates he entered the university unprepared to take on the rigors of higher education. However, the masters at Cambridge clearly believed in his natural intelligence, and allowed him to take the extra years he needed, whatever the reason.

He completed his Master's degree in the standard time. After he completed his Master's degree, he married, despite having agreed to take religious orders and despite the knowledge that marriage would forfeit a fellowship he was awarded by Cambridge. When his wife died giving birth to their first child, the university again offered Cranmer the fellowship, which he accepted. At this point he began theological studies and within a few years received holy orders. He eventually earned a doctorate degree in divinity, in 1526.

His devotion to the church did not preclude an interest in serious church reform, though he was not supportive of Martin Luther, according to recent scholarship. He made his first contact with Henry VIII when he returned from participation in an English embassy to Spain. According to letters written by Cranmer, he met with Henry privately for half an hour, and described him as "the kindest of princes." That initial meeting may have helped Cranmer catch the king's eye, but it was a few years later, when Henry was desperately looking for ways to end his marriage to Catherine of Aragon, that truly drew Cranmer to Henry's attention.

In the summer of 1529, Cranmer was staying with some friends in the country, joined by some former fellow students from Cambridge. Much of their conversation concerned theology, reform, and of course, the king's "great problem." Cranmer speculated that if Henry could indeed make the case that by marrying his dead brother's wife he was committing incest, then the lower ecclesiastical courts could handle the matter entirely, with no need for Papal intervention. Henry happened to be visiting nearby as well, and heard of Cranmer's comments. Cranmer was summoned to the king shortly thereafter, and a plan was organized and implemented for a committee to visit locations in Europe to discuss the matter with a number of theologians.

During his travels he met and married Margarete a niece of German reformer, Andreas Osiander. Naturally, he had to lay aside his holy orders to do so. While still on his travels he received word that Henry had appointed him Archbishop of Canterbury. The appointment was on the behalf and recommendation of the Boleyn family, of whom Anne, was Henry's chief reason for divorcing Catherine. Therefore, Cranmer returned to England to take his new position. During the ensuing months Cranmer worked closely with the king and his advisers to enact England's official break from Rome, and the establishment of the Church of England, with Henry as its head. In the meantime, Cranmer officiated at Anne and Henry's wedding as well as her coronation. It was a very risky and dangerous time for all involved. Cranmer continued to play a prominent role at court and the English church. When Henry died, his young son, Edward VI assumed the throne and Cranmer continued to enjoy high status.

He also continued to implement further Protestant reform, with the young king's (and his advisers) full approval. He is chiefly responsible for the development, organization, and publication of the English Book of Common Prayer. When the young king took ill in 1553, Cranmer and other members of the council moved swiftly to protect their own interests, and the numerous reforms they had enacted. Their plan was to place the young, malleable, and Protestant Lady Jane Grey on the throne, should Edward die. They convinced Edward to change his will to exclude his two half-sisters, Mary and Elizabeth, from the succession to the throne. The plan failed miserably, and the very Catholic Mary's supporters overtook those defending Jane and her Protestant followers.

Cranmer and a number of others were sent to the Tower to await trial for treason. In November of the same year, a trial was held and the group, including Cranmer, was found guilty and condemned to death. Then the waiting began. He was transferred to other prisons, and given multiple opportunities to recant. This he did, though clearly he was not following his conscience, and was considered by some observers to be a "broken man." Technically, Mary should have absolved him, as he had not only recanted but participated in the Mass and Holy Communion. But, Mary was in a hurry, she wanted to purge her kingdom of all reformists. He was ordered burned at the stake, but that he would have a chance to recant in public.

He submitted a script, which was accepted as appropriate. However, on the date of his execution, he deviated from what he had submitted. He renounced his earlier recantations, and said, "And as for the pope, I refuse him, as Christ's enemy, and Antichrist with all his false doctrine." At this point he was forced from the podium, tied to the stake, and set ablaze. His final words were reported as "Lord Jesus, receive my spirit...I see the heavens open and Jesus standing at the right hand of God."