Conversation so far:
What happpened at the valley and apomattox with George Armstrong Custer?
George Armstrong Custer led his Wolverines to Shenandoah Valley where by the year's end they defeated the army of Confederate Lieutenant General Jubal Early in the Valley Campaigns of 1864.

Question: How did they defeat the army?
Self-contained rewrite: How did Sheridan and Custer defeat the army of Confederate Lieutenant General Jubal?