Final answer:
The statement is true; the Emancipation Proclamation did not immediately free every slave as it only applied to rebellious states and excluded border states and Union-held areas.
Step-by-step explanation:
The statement that the Emancipation Proclamation, signed by Lincoln on January 1, 1863, did not free every slave is true. Although it declared that all persons held as slaves in the rebellious states would be free, it did not apply to slave-holding border states and areas under Union control. These exclusions meant that the proclamation did not immediately have any legal effect on the status of enslaved people in the Confederacy, where the Union could not enforce it, nor did it apply to Union-held territories or border states like Kentucky, Maryland, Delaware, and Missouri that had not seceded. The proclamation was as much a war strategy directed against Confederate resources as it was a step towards freedom. It redefined the Civil War to include a new revolutionary war aim: the overthrow of slavery by force of arms. Lincoln hoped that by declaring the enslaved people in the rebelling states to be free, he would weaken the Confederacy's war effort and provide momentum for a broader abolition of slavery.