People in the Middle Ages had various beliefs and took different actions in response to the bubonic plague: - They believed the plague was caused by planetary alignment and God's anger, and was spread through bad air and direct contact. - To address this, they carried herbs, isolated the sick, prayed, went on pilgrimages, burned incense and clothes, and avoided dirty areas. - Some participated in flagellation processions, whipping themselves to show remorse and ask God for forgiveness, hoping it would make the plague go away.