Lincoln's plan for reconstruction required former confederate states to do three things in order to be readmitted into the union. what were they? states had to imprison former confederate leaders. they had to promise to never again secede from the country. they had to swear an oath of allegiance to the united states. ten percent of the states' voters had to want back in. they had to pay restitution for all civil war losses and damages. each state had to abolish the institution of slavery.