England and France both wanted Florida. They wanted Florida so they could have more land in North America. In the 1600s, English settlers moved into Carolina, then part of Spanish Florida. So they attacked Spanish settlements.
The United States now wanted control of Florida. Spain's attempt to bring settlers to Florida failed, and by 1800 Spain's control of Florida had weakened. Gaining control of Florida for the United States would mean gaining control of the Mississippi River. That was an important route for trade.
Answer: The St. Bartholomew's Day massacre in 1572 was a targeted group of assassinations and a wave of Catholic mob violence, directed against the Huguenots