A) President Lincoln issued the Emancipation Proclamation, in January 1863, during the Civil War. The document declared the freedom of all of the Slaves in the States that belong to the Country. This didn´t, however, did not affect the legal status of slaves in states who were in rebellion (the Confederacy).
B) President Lincoln highly criticized the legislation made by the US Congress such as the Kansas-Nebraska Act of 1854, which let settlers decide whether or not they would permit slavery in these territories. He also opposed the Missouri Compromise, which accepted the Status of Missouri as a slave state in exchange for having Maine as a "free" state.
C) Slaves received uniforms and were armed in order to perform as soldiers of the Union in the Civil War. As a response, Jefferson Davis declared the "Anti Emancipation" proclamation, which stated that any black mas found in uniform will immediately be captured and returned to slavery.