In 1037 the Seljuk Turks established an empire in the Middle East. Seljuk power threatened the Byzantine Empire by 1093 leading the emperor to solicit help from Pope Urban II. Urban responded by calling for the first Crusade to free Jerusalem from Muslim rule. The first Crusade set off in 1096 and lasted until 1099. The Crusaders successfully drove the Turks from Jerusalem and established four small Christian kingdoms in the Middle East. This success was short lived however, in less than 100 years Jerusalem was back in the hands of the Muslim Turks. The Christians of Europe organized several other Crusades over the next 300 years but none of them were ever able to retake Jerusalem. Motivation for the Crusades was a mix of genuine religious zealotry, economic self-interest, and political opportunism. Devout Christians found motivation in the fact that the Seljuk Turks denied Christian pilgrims access to Jerusalem and the pope’s promise of guaranteed salvation for all those who died on Crusade. Those seeking economic advantage hoped that the Crusades would offer opportunities for booty and land. This was particularly inviting to the younger sons of nobles. Under feudal tradition, the oldest son inherited his father’s land and titles leaving little opportunity to younger brothers. The Crusades offered these young men a chance to obtain land and titles in newly conquered territory. Italian merchants sought profit from financing and transporting Crusader armies and hoped that success on the battlefield would bring Christian control of lucrative trade routes. The popes hoped that the Crusades would bring peace to Europe by uniting quarreling knights against a common enemy abroad and reinforce the power of the papacy in secular affairs.
While the stated goals of the Crusades were only realized for a brief period the other effect of these endeavors on Europe long endured. The Crusades stimulated Mediterranean trade. The coastal Crusader states established in the first Crusade facilitated trade between Asia and Europe and the exposure of Europeans to Asian goods while on Crusade increased demand for these commodities. Europeans were also exposed to Muslim scholarship while on Crusade. This scholarship included the translated works of many of the classical Greek philosophers. Many of these works had largely been forgotten in Europe and were only rediscovered by Europeans by way of Arab translations. Arab, Persian, and Greek scholarship helped spur and intellectual awakening in Europe in the early 15th century. The Crusades also helped to undermine the feudal order in Europe. The Crusades offered opportunities to all levels of society. Kings found greater power and influence as the armies consolidated under their leadership. Serfs gained freedom and sometimes wealth from participating in Crusades. A few lucky nobles gained titles and land in the short-lived Crusader States.
To the east, the Crusades left a legacy of animosity. During the fourth Crusade, motivated by economic opportunity, Weste European Christians sacked and looted Constantinople. This attack only increased the divide between the Roman Catholic Church in the West and the Easte Orthodox Church. Years later in the 19th and 20th century the history of the European Crusades against the Muslim world became a tool of Turkish and Arab nationalism.