In issuing more significant encyclicals and visiting more nations than any other pope, he's shown that Christianity remains a world force.

Elected to be a caretaker pope, he decided instead to revolutionize Catholicism.

Luther and Calvin challenged the Catholic church on many key teachings—but not on the doctrine of last things.

An Orthodox archbishop on the Catholic pope.

Why followers of the Prince of Peace waged war.

The great preachers, planners, and fighters of the Holy Land crusades.

Christians thought they had liberated Jerusalem from infidels. But what did Muslims think?

He bequeathed statements of belief that guide millions of Christians today.

What has Luther left to us, 500 years later?

After Luther published these three works, there was no turning back.

Luther made plenty of both

She lived only 33 years, but her vibrant faith and writings were so influential she has been declared a Doctor of the Church.