In 1096, a huge army of monarchs, nobles, hedge knights, farmers and citizens moved over land to Anatolia and Syria via Constantinople. Here, the crusaders (participants of a crusade) fought through Turkish areas.
After three years, they reached Jerusalem. At that time, the city was no longer controlled by Turks, but by Arabs. The crusaders entered the city and slaughtered Muslims and Jews.
After Jerusalem, the crusaders also conquered areas along the east coast of the Mediterranean Sea. They created four crusader states where they lived and started to rule the local people.