Nicholas
The greatest Union casualties caused by Confederate forces outside of Gettysburg were on a lesser known battlefield at Spotsylvania on May 8-21, 1864. Confederate forces lead by Lee were outnumbered 2-to-1. Grant’s advances continued to be fruitless and ineffective. The series of carefully orchestrated movements on both parts made the victory status a draw, as both sides contested victory. However, the casualties suffered by Union forces under Grant and Meade reached 18,399 killed, wounded, or captured. Confederate forces suffered 12,687 among the dead, wounded or captured. It was the costliest battle of the campaign for the Union since the start of the war.
