What event is considered to be the spark or starting point of the crusades?

This was an order issued during the civil war by president lincoln ending slavery in the confederate states

How did african americans the union during the civil war? a. by serving as representatives in congress b. by enlisting in the military to fight c. by organizing massive slave revolts in the south d. by negotiating for peace with the confederacy

When lincoln was first elected president, he hoped to prevent war by allowing (1) in the united states.