Do you think it can be argued that in the middle of the century Christianity played a major role?
The worldview of a man of the Middle Ages was highly dependent on religion. Christianity at that time was not just a religion, but an ideology that regulated the daily life of a person, and also shaped his views of the world.
Also, Christian doctrine rejected scientific discoveries, and the fires of the Inquisition were burning throughout Europe. Going beyond the usual, measured life, violation of the canons established by the Christian Church was severely punished. The people read little, and if they knew how, they read mainly theological books, there were simply no others. Because of this, the sermons of the priests were the main source of knowledge of the world from childhood.
Thus, it can be argued with full confidence that Christianity played an important role in the Middle Ages.