Complex sentence: His complex moves toward ending slavery centered on the Emancipation Proclamation in 1863, using the Army to protect escaped slaves, encouraging the border states to outlaw slavery, and helping push through Congress the Thirteenth Amendment to the United States Constitution, which permanently outlawed slavery.
Split into simpler sentences: His complex moves toward ending slavery centered on the Emancipation Proclamation of 1863. Lincoln used the U.S. Army to protect escaped slaves, encouraged the border states to outlaw slavery, and helped push through Congress the Thirteenth Amendment to the United States Constitution, which permanently outlawed slavery.