Why did the crusaders crusade?

Answer 1

There were several reasons that crusaders had for joining the crusade.

1) Wealth-many went over for gaining wealth from the gold and money that the Muslims had.

2) Glory- many went over thinking that if they killed as many Muslims they could, that they would have all the glory.

3)Forgivness- many went to Jerusalem to seek forgivness from their sins.

4) Religion- many went to bring their religion to the Muslims and thought that they could make them repent from their heathen ways.

Answer

The above is entirely correct however, the Crusades were about more than just "conversion".

The fundamental "reason" for the crusades was that when the Muslims took over the Holy Land (Palestine/Israel), they forced many of the Jews and Christians out of the churces, temples and holy sites and converted many of them into mosques and other Islamic sites. While the Crusaders didn't care about the Jews being kicked out, they were certainly annoyed that it happened to the Christians, and so the Crusades began as a "Christian reclaimation" of the Holy Land. And even the "conversions" usually happened at the point of a sword.