The Crusades began in 1095 with the launching of the First Crusade and continued for over two hundred and fifty years. There were many Crusades, but I do not think I could list them all with their defining characteristics in this small space. The major Crusades included the First Crusade whose defining characteristic was that they really believed in the Crusading Ideal. The wanted to take Jerusalem back into Christian hands. For centuries the Muslims had ruled Jerusalem, making it difficult for the Christians who lived there and for pilgrims to journey there. The First Crusade established the Latin Kingdom of Jerusalem as well as other Crusader states. The Crusade of 1101 was mostly defined by its failure. The Second Crusade was also marked by failure and was defined by the weakness and poor judgement of Louis VII of France. The Third Crusade was defined by the unity of the Muslim world of Saladin and the diplomacy of Richard II in coming to an agreement with him. The Fourth Crusade never made it to Jerusalem because it began attacking fellow Christians in Greece. The Children's Crusade was a group of children who left Europe never to be heard from again. The Seventh and Eighth Crusades were led by Louis IX and barely held a foothold in the Levant against overwhelming odds.

As you see, there is a great deal of Crusading history. I have referred some web sites below.