Final answer:
The final military actions of the Civil War led to a Union victory through the defeat of General Lee at Gettysburg, the capture of Vicksburg by Grant, and the Confederacy losing support and resources.
Step-by-step explanation:
The final military actions of the Civil War led to a union victory due to several factors. First, the Union Army defeated the Confederates led by General Robert E. Lee at the Battle of Gettysburg, which ended the Confederate invasion of the North. Second, Union General Ulysses S. Grant captured Vicksburg, Mississippi, gaining control of the Mississippi River and dividing the Confederacy.
Lastly, the Confederate forces lost support from foreign countries and faced a long war with limited resources and no allies. The combination of these Union victories drained Confederate resources and morale, leading to Confederate General Lee's surrender at Appomattox Court House on April 9, 1865.