There were over 3 million men that fought in the Civil War with a combined death toll estimated to be around 620,000 men. The American Civil War is the deadliest war in American history with more causalities than World War 1 and World War 2 combined. The Highest Ranking officer killed in action was General (Full General) Albert Sidney Johnston at the Battle of Shiloh. More soldiers died to disease than were killed in action which illustrates the dangers a soldier faced during this time period.
The 483,026 total Confederate casualties have been divided accordingly:
Numbers taken from National Park Service: Civil War Facts.
The total amount of military personnel for the Confederate armies and navies over the course of the war was between 750,000 and 1,227,890 personnel. Since records were destroyed there is not a definitive number for the personnel involved for the Confederacy. With the armies being the strongest in 1863 with around 300,000 personnel, this number includes volunteers, conscripts, and professional military personnel. Some volunteers and conscripts served short military stints, 90 day and 3 year obligations are two examples.
The 642,427 total Union casualties have been divided accordingly:
Numbers taken from National Park Service: Civil War Facts
The total amount of military personnel for the Union armies and navies over the course of the war was 2,672,341 personnel. With the armies being the strongest in 1863 with around 600,000 personnel this number, stayed consistent through the end of the war. This number includes volunteers, conscripts, and professional military personnel. Some volunteers and conscripts served short military stints 90 day and 3 year obligations are two examples.