Final answer:
The preliminary Emancipation Proclamation, issued on September 22, 1862, stated that slaves in rebellious areas were now free. It was seen as a military necessity for preserving the Union.
Step-by-step explanation:
The preliminary Emancipation Proclamation, issued by Abraham Lincoln on September 22, 1862, stated that the slaves in areas still in rebellion against the United States were "henceforth and forever free." This proclamation was seen as a military necessity to preserve the Union. It also called for voluntary colonization of freed slaves and encouraged loyal states to implement gradual emancipation.