Cranmer was appointed to the See of Canterbury by the Pope and consecrated as such on March 30, 1533. Nevertheless, he had studied the new (Lutheran) Reformation doctrines intensely while at Cambridge, and became responsible, to a great degree, for the Reformation within England. Of course, his involvement with the annulment of King Henry's marriage to Catherine of Aragon, and the King's subsequent marriage to Anne Boleyn did not play well in Rome. Additionally, Cranmer believed the King was supreme, not only in civil matters, but also in religious matters, and the Church of England soon broke from the Roman Church.
Under King Edward the Sixth, Cranmer was free to shape the worship, doctrines and practices of the Church of England. Most importantly, Thomas Cranmer was responsible for the very first Book of Common Prayer in 1549, as well as its revision in 1552. All subsequent Books of Common Prayer throughout the Anglican Communion, including John Wesley's The Sunday Service of the Methodists in North America, look back to Cranmer's Prayer Book, and all who use a version of the Book of Common Prayer or a liturgy that has been influence by one of the Prayer Books owe an immeasurable debt to Thomas Cranmer.
Even non-liturgical Nazarenes owe an immense debt to Cranmer. Our own ritual for the Lord's Supper in our Manual (Book of Discipline) was an abbreviated form of the Methodist Episcopal ritual, which came from Wesley's Sunday Service, which was a version of the Book of Common Prayer of the Church of England. Closer to home, Wesley's understanding of holiness was, in many ways, shaped and supported by the liturgy of the Anglican Church, and the Collect of Purity at the beginning of the Communion service has been said to encapsulate our understanding of holiness.
Let us give thanks to God for "Grandpa" Thomas Cranmer, Archbishop of Canterbury! (For more information, see Lesser Feasts and Fasts - 1997.)