Crusades occurred between Muslims and Christians in 1097 to 1291, which its main aim was to recapture Jerusalem by the Christians. During this time, Europeans had enough opportunity to learn about Islamic civilization and its cultural and economic benefits. Although these were ended with the political and military victory of Muslims enabling them to keep their lands, Europeans were much benefited of the economy, culture and civilization. Crusades caused Europeans to be familiar with the East and especially the glorious Islamic civilization and they took advantage of Muslims’ knowledge. This leads to developments that this later had an important role in the Europe progress. In fact the Crusades caused the transfer of achievements of Islamic civilization into Europe. The objectives of this study are as follow: it reviews the development of Europe after the Crusades, using rich culture and civilization of Islam and it investigates the stagnation of the Islam after the Crusades. That period is considered to be one of the most important liaison points. Although the crusaders came to the Islamic oriental seeking war rather than knowledge, they were influenced by Islamic civilization. The crusaders benefited as much as they could of the Muslims’ achievements to Europe, which was suffering from backwardness and degeneration at that time. This study analyzes the appropriate responses to the following questions: Though the Europeans were trying to understand the Muslim community by establishing Islam and Orientalism studies and even teaching Arabic and Persian in their universities, why Muslims did not stepped towards understanding west in the same manner? Although Islamic culture had an outstanding effect on the growth of European intellectual, it was still virtually challenging to have mutual understanding among civilizations.