There were at least nine Crusades that took place between the 11th and 13th centuries when troops representing the Roman Catholic Church attempted to spread Christianity into regions of the Middle East.
First Crusade (1095-1099). Pope Urban II called for troops to battle the Seljuk Turks, and the Christian armies were victorious at Nicaea and Antioch. Godfrey of Bouillon led the Crusader army which captured Jerusalem.
Second Crusade (1147-1149). Christian armies failed to retake Muslim territories in the Middle East, and Damascus eventually fell to the Crusaders' enemy Nur ad-Din Zangi. But the Christians reclaimed Lisbon and parts of Spain from the Muslims.
Third Crusade (1187-1192). After Jerusalem fell to Saladin, Pope Gregory VIII called for another Christian invasion. The famed British King Richard I (the Lionheart) won victories at Cyprus, Acre (Israel), Arsuf (Israel) and Jaffa (Tel Aviv), but Richard did not believe he would be able to hold Jerusalem if captured.
Fourth Crusade (1202-1204). Armies organized by Pope Innocent III sacked Constantinople.
Fifth Crusade (1217-1221). The Christians were defeated by Egyptian Ayubid Sultan Al-Kamil, who negotiated a peace treaty with the Europeans. Al-Kamil later met with St. Francis of Assisi, who had ventured through the lines to meet with the Sultan.
Sixth Crusade (1228-1229). Emperor Frederick II of the Holy Roman Empire succeeded in retaking Jerusalem, Nazareth and Bethlehem afte negotiating a treaty with Al-Kamil.
Seventh Crusade (1248-1254). The Templars initiated this crusade, and they were badly defeated at the battle of La Forbie in Gaza. A French Crusade led by King Louis IX of France was also a failure.
Eighth Crusade (1270). King Louis IX also led the unsuccessful invasion of Tunis; the king died after just a few months.
Ninth Crusade (1271-1272). Led by England's Edward I, the ninth Crusade was an unsuccessful one--and the final invasion by Europeans of the Middle East.