Maps: Crusades (1095–1291)

"In the 7th century AD, a Muslim Jihad had spread out of Arabia across the Mediterranean world, conquering about half of the Christian world, including the holy city of Jerusalem. The early Muslim rulers of this vast empire were relatively tolerant of Christianity and Judaism, which were seen as other Abrahamic faiths, preferable to Paganism under Islamic law. The Christians and Jews were thus given permission to practice their religion as long as they paid the Jizya, a special tax levied on non-Muslims. From the 7th to the 9th centuries, the Christian world was comparably weak and unable to recuperate any of the territories lost to the Muslims. However, by the 10th Century, the Christians began to recuperate and reclaim these lands."
The Crusades in the Holy Land
MetMuseum: The Crusades (1095–1291)
The Crusades - Introduction