In his quest for spiritual peace, Luther had no idea he'd leave his world in turmoil.

If Jesus was truly God, how could he be truly human as well? Leo the Great helped guide a critical council to a clear answer.

Long-standing differences between Western and Eastern Christians finally caused a definitive break, and Roman Catholics and Eastern Orthodox still remain separate.

The massive treatise set forth a theological system so influential it has been declared eternally valid.

A selective chronological listing

Breaking from Rome, the English Parliament declared King Henry VIII "the only supreme head on earth of the Church of England."

Responding to the Reformation, the council charted the Catholic church's course for the next 400 years.

In an epochal council, the Catholic Church undertook its most searching self-examination ever and renewed itself for a modern world.

A brief listing of significant dates that also earn a place in the "Christian History 100"

True and False Leaders(1539)