In the 300s CE, Christianity and writing were both brought to Ireland. Saint Patrick was famous for spreading Christianity in Ireland in the 400s, but he was not the first Christian in Ireland. For the next 300-400 years, more Irish people became Christian. Christian monks from other countries came to Irish monasteries. Some monasteries grew into towns. The main buildings from 400-800 CE were round forts (raths or ringforts) made of dirt, with houses inside. Most of the forests were cut down to make farms. There were some new kingdoms in this time. The kingdom of Uí Néill in north Ireland took over the area called Tara, then ruled over all the other kingdoms. They were called the high kings.