The Crusades were a series of religious wars between Christians and Muslims started primarily to secure control of holy sites considered sacred by both groups.
Step-by-step explanation:
There were at least eight Crusades. The First Crusade lasted from 1096 to 1099. The Second Crusade began in 1147 and ended in 1149. The Third Crusade started in 1189 and was concluded in 1192. The Fourth Crusade got underway in 1202 and ended in 1204. The Fifth Crusade lasted from 1217 until 1221. The Sixth Crusade occurred in 1228–29. The Seventh Crusade began in 1248 and ended in 1254. And the Eighth Crusade took place in 1270. There were also smaller Crusades against dissident Christian sects within Europe, including the Albigensian Crusade (1209–29). The so-called People’s Crusade occurred in response to Pope Urban II’s call for the First Crusade, and the Children’s Crusade took place in 1212.
Crusades, military expeditions, beginning in the late 11th century, that were organized by western European Christians in response to centuries of Muslim wars of expansion. Their objectives were to check the spread of Islam, to retake control of the Holy Land in the eastern Mediterranean, to conquer pagan areas, and to recapture formerly Christian territories; they were seen by many of their participants as a means of redemption and expiation for sins. Between 1095, when the First Crusade was launched, and 1291, when the Latin Christians were finally expelled from their kingdom in Syria, there were numerous expeditions to the Holy Land, to Spain, and even to the Baltic; the Crusades continued for several centuries after 1291. Crusading declined rapidly during the 16th century with the advent of the Protestant Reformation and the decline of papal authority.
Approximately two-thirds of the ancient Christian world had been conquered by Muslims by the end of the 11th century, including the important regions of Palestine, Syria, Egypt, and Anatolia. The Crusades, attempting to check this advance, initially enjoyed success, founding a Christian state in Palestine and Syria, but the continued growth of Islamic states ultimately reversed those gains. By the 14th century the Ottoman Turks had established themselves in the Balkans and would penetrate deeper into Europe despite repeated efforts to repulse them.