Here's why:
* Deeply religious: Louis IX was known for his unwavering faith. He was a strong supporter of the Church and dedicated much of his life to religious practices.
* Crusades: He led two crusades to the Holy Land, demonstrating his commitment to defending the faith.
* Canonization: He was canonized by the Catholic Church in 1297, recognizing his piety and holiness.
It's important to note that while Louis IX was a devout Catholic, his reign wasn't without its controversies. Some of his actions, such as the persecution of heretics, are seen as harsh by modern standards. However, his deep religious faith and his legacy as a holy king remain a significant part of his historical identity.