 In 1864, at the Battle of Monocacy, Wallace commanded a 5,800 man force to oppose Jubal Early's 14,000-man invasion of Maryland.Faced against an army more than twice his size, Wallace was eventually forced to retreat to Baltimore, but his men delayed Early's advance for a full day, enabling Union re-enforcement to be brought up to protect Washington D.C.Despite this success and later fame for writing the book "", criticism of Wallace's conduct at Shiloh would haunt him for the rest of his life and he would spend much of it trying to defend his actions there.