Complex sentence: With the conversion of the land to Christianity around 1100 AD, Sweden entered the Middle Ages, during which monastic writers preferred to use Latin, which means there are only a few texts in the Old Swedish from that period.
Split into simpler sentences: With the conversion of the land to Christianity around 1100 AD, Sweden entered the Middle Ages, during which monastic writers preferred to use Latin. Therefore there are only a few texts in the Old Swedish from that period.