When Crusades are thought of, majority of people only thinks of various European expeditions mounted to reconquer the Holy Land from the Muslims. During this period, the armor would have been various types of mail. In the First Crusade, knights would have looked no different from Norman knights of the Bayeux tapestry, depicted below:

During 12th century, so era of Second to Fourth crusades, knights would have looked roughly as Crusaders are most often depicted in popular media, so basically like knights below:

Later crusades happened in 15th and 16th centuries. Unlike “numbered” Crusades (First to Ninth), these Crusades were not aimed at liberating the Holy Land from Muslim occupation. Rather, they were aimed at slowing down or stopping the Ottoman conquest in Europe. A knight of Varna and Kosovo crusades (1444 and 1448, respectively) will have looked like this:

Later Crusades were also aimed at defense against the Ottomans, but were usually called Holy Leagues since they were formal alliances between states rather than religiously inspired military movements of nobility and lords. Most famous of these was the Holy League that won the Battle of Lepanto in 1571. An officer at Battle of Lepanto will have looked like this:

Last Holy League was formed in 1717, between Portugal, Venice and the Papal States, in order to contain the Ottoman naval activity to the Eastern Mediterranean. Portuguese soldiers of the time will have looked roughly like this:

As can be seen from the above, there is no single answer to the “armor of the Crusaders” as the Crusades cover a very, very long period of time. Armor evolved and adapted over this time period, as metallurgy improved and new weapons developed, thus necessitating improved defenses.

• armor
• medieval
• technology