The Black Death arrived in 1348 from Eastern Europe/Asia via fleas on trading ships. People rapidly became ill with symptoms like fever, headaches, vomiting, and swollen lymph nodes. Approximately 70% of people died from either the bubonic or pneumonic forms of plague. While the exact cause was unknown, people believed it was caused by things like God's punishment, foul air, or imbalanced bodily humors. Treatments included bleeding, purging, avoiding bad smells, cleaning towns, and acts of penance like self-flagellation. The plague demonstrated that both natural and supernatural ideas about medicine and disease remained influential.