The Middle Ages were all about converting the world to Christianity and maintaining a strong belief in the power of god. explain:The...

We cannot fully answer this question for you because it is
your assignment. You are going to have to do some research into Christianity in the
Middle Ages. When you do, you will find that the movements you mention are major
examples of how Christianity manifested itself in the Middle Ages. The rise of any other
great religion, such as Islam, was a threat to Christianity because Christians believed
(and still do) that the only way to heaven was through Jesus. Not being allowed to
practice their faith would have been akin to death, and in Islam during this period,
Christians were likewise viewed as infidels. So, whoever was stronger would win and
neither one of these religions would be able to tolerate the other being in
power.

For example, the Crusades were mostly futile attemts
to recapture the Holy Land from the Muslims. Christians believed that Muslims were
infidels and it was sacrilege for them to be in possession of lands where Jesus walked.
Many of the popes and kings of Europe believed they would obtain glory on earth AND in
heaven if they went on Crusades and converted the infidels to Christianity. Almost all
of the Crusades were failures, however - in conversion success and in the goal to
recapture the Holy Land.

Pilgrimages were voyages to holy
shrines that Christians went on, again, in hopes of improving things for themselves when
they got to heaven. They believed that God would bless them in a special way. Churches
and cathedrals built during the Middle Ages were also constructed in the hope that God
would grant the builders special favor in heaven. The architecture reflected the glory
of God, and the decorations and stained glass windows, flying buttresses, etc. were very
beautiful, but they were built by man, not God, and were examples of worshipping the
creation, not the creator. 

Christianity during the Middle
Ages was very works-oriented, so people believed that THEY had to earn their salvation.
This is why they did so many of these works-related things like Crusades, Pilgrimages,
building cathedrals, etc. It was not until the Protestant Reformation, much later, that
Martin Luther and others pointed out that salvation was obtained, as St. Paul pointed
out, through grace, not works (Ephesians 2:8-10).

This is a
general overview of the situation, but you must dig up the facts and examples yourself.
Good luck!