The Catholic Church was the only church in Europe during the Middle Ages, and it had its own laws and large coffers. Church leaders such as bishops and archbishops sat on the king's council and played leading roles in government. Bishops, who were often wealthy and came from noble families, ruled over groups of parishes called "diocese." Parish priests, on the other hand, came from humbler backgrounds and often had little education. The village priest tended to the sick and indi. As the population of Europe expanded in the twelfth century, the churches that had been built in the Roman style with round-arched roofs became too small. Some of the grand cathedrals, strained to their structural limits by their creators' drive to build higher and larger, collapsed within a century or less of their construction. gent and, if he was able, taught Latin and the Bible to the youth of the village.