Europeans carried a hidden enemy to the Indians: new diseases. Native peoples of America had no immunity to the diseases that European explorers and colonists brought with them. Diseases such as smallpox, influenza, measles, and even chicken pox proved deadly to American Indians.
As they did not understand the biology of the disease, many people believe that the black death was a kind of divine punishment retribution for sins against god such as greed, blasphemy, heresy, fornication and worldliness. By this logic, the only way to overcome the plague was to win God‘s forgiveness.
Economic troubles, weak leader, and National Assembly