I'm pretty positive it was the Egyptians.
Hope this helps! :)
Fighting a defensive war.
Robert E. Lee wanted to take the war to the Union, on Union ground. Most of his victories had been in or near Army of Virginia home soil.
Going north was an attempt to shorten the war as he knew a prolonged war of attrition favored the industrial and populous north.
Father against son, brother against brother. A very sad time.
