In December of 1863, Lincoln issued a Proclamation of Amnesty and
Reconstruction which gave really an olive branch to Confederate states that
wished to rejoin the Union, even though the Civil War wasn’t quite over,
yet.  This proclamation allowed for the consideration of readmission to
take place if ten percent of a state’s voters took an oath of loyalty to
the Union and if other conditions were met, namely the abolition of slavery
and respect for the laws of the United States.