Please read EITHER
Mike Paine, The Crusades (Pocket Essential, 2001), 7-46. Available as an e-book in the Drexel Library catalogue at: http://site.ebrary.com.ezproxy2.library.drexel.edu/lib/drexel/detail.action?docID=10005847
OR
Peter Frankopan, The First Crusade: The Call from the East (Cambridge: Harvard University Press 2012); Available as an e-book in the Drexel Library catalogue at: http://site.ebrary.com.ezproxy2.library.drexel.edu/lib/drexel/detail.action?docID=10568046
And then discuss: What impact does your author think the Crusades had on the relationship between Western Europe and the rest of Eurasia between 1000-1200. NOTE: Frankopans more recent account (2012) shows the important role the Ottoman empire played in starting the Crusades.