The Crusades are among the most polarizing historical events in the popular imagination. Few historical events are brought up so frequently and yet are so poorly understood as the Crusades. In this question, first discuss in detail the historical conditions that contributed to the preaching of the first crusade.
Next, describe the main themes that Urban II uses to motivate his hearers in Robert the Monk's record of Urban's speech at Clermont and explain why those themes might be convincing to the audience.
Finally, given the events of the previous decades, why might Urban have good political reasons to commission an army that took an oath to St. Peter?