What was one effect of the Crusades?

Answer 1

Legacy

In Europe:
The Crusades have been remembered relatively favourably in western Europe (countries which were, at the time of the Crusades, Roman Catholic countries). (Nonetheless, there have certainly been many vocal critics of the Crusades in Western Europe since the Renaissance.)


Regarding Politics and culture:
The Crusades had an enormous influence on the European Middle Ages. At times, much of the continent was united under a powerful Papacy, but by the 14th century, the development of centralized bureaucracies (the foundation of the modern nation-state) was well on its way in France, England, Burgundy, Portugal, Castile, and Aragon partly because of the dominance of the church at the beginning of the crusading era.

Although Europe had been exposed to Islamic culture for centuries through contacts in Iberian Peninsula and Sicily, much knowledge in areas such as science, medicine, and architecture was transferred from the Islamic to the western world during the crusade era.

The military experiences of the crusades also had their effects in Europe; for example, European castles became massive stone structures as they were in the east, rather than smaller wooden buildings as they had typically been in the past.

In addition, the Crusades are seen as having opened up European culture to the world, especially Asia.

Along with trade, new scientific discoveries and inventions made their way east or west. Arabic advances (including the development of algebra, optics, and refinement of engineering) made their way west and sped the course of advancement in European universities that led to the Renaissance in later centuries.

The invasions of German crusaders prevented formation of the large Lithuanian state incorporating all Baltic nations and tribes. Lithuania was destined to become small country and forced to expand to the East looking for resources for wars with crusaders.

Answer 2

It was pretty messed up. It had the effect of showing me that there is no good in any organized religion that is of humans.
I will take my god(s) with there flaws and there funny songs even if I am the only one that can see them, and I will not ever kill another to save convince them which of my god(s) is the funniest.
After I learned of the Crusades it sickened me. All parties that took place in them, attackers and defenders were lunatics.