The Northern Strategy (Anaconda Plan), defensive tactics, and enlistment of African Americans were key elements of the Union victory in the Civil War.
The key strategy that was a crucial element of the Union victory in the Civil War was the Northern Strategy known as the Anaconda Plan. This plan involved a Union blockade of main ports to strangle the rebel economy and the capture of the Mississippi River to split the South, ultimately weakening the Confederacy.
Additionally, the Union's ability to hold defensive positions, strategically attacking the flanks of the Confederate forces before going up the middle, played a significant role in their victory.
Furthermore, the enlistment of free African Americans in the Union military, despite initial hesitations from Lincoln, bolstered the Union forces and contributed to their success.