This is a good question.
Dr. David Anders, former Calvinist, and church historian likes to bring up the point that Protestantism is very particular. As it didn’t happen in Syriac East, the Greek East, or Coptic, or Chaldean, or Syro-Malabar India, or any of the other apostolic communities… except in a very particular sliver of Europe.
That’s very suggestive that maybe more was going on than just a faith-based motive to reform the church, as all the apostolic traditions have most essentials in common with Roman Catholicism.
Well, if you look at it from the political perspective, the Eastern strains of Christianity retained the Caesaro-Papism of the Christian Period of the Roman Empire. In other words, in the Orthodox tradition, the notion of the Church being subservient to the Emperor was retained, and indeed, the Byzantine Emperors were viewed very specifically as spiritual as well as temporal ruler. This was in keeping with Constantine’s views on the Emperor’s role in the Church.
In the West, after the fall of the Roman Empire, the Western Church evolved in a decidedly different direction, particular in the late Middle Ages, where the Papacy essentially asserted supremacy over the Christian princes. Crises like the Investiture Controversy, which were, as I said above, fundamentally a struggle between the German Holy Roman Emperors and the Papacy, created a considerable amount of ill will towards the Church. In England, we saw similar battles, such as the humiliation of Henry II and the almost immediate canonization of Thomas Becket (despite the fact that no one actually believed Henry meant to give an order to kill the Arch-Bishop, and even Becket’s allies thought him an extremist).
Thus we begin to see a strain between the Papacy and the German princes that never quite healed. Couple that with the other real and imagined abuses of the Papacy, you can see why the German princes leaped at Martin Luther’s Theses. Creating national churches that forswore any allegiance to Rome, and in many cases, even to Catholic doctrine and custom, ended what they viewed as undue Papal meddling. Even Henry VIII of England, while still theologically Catholic, certainly saw the value in the opportunity of a break with Rome.