His books include those of Timeline 191 ( a.k.a. Southern Victory , also known as TL-191 ) , in which , while the Confederate States of America won the American Civil War , the Union and German Empire defeat the Entente Powers in the two Great War s of the 1910s and 1940s ( with a Nazi-esque Confederate government attempting to exterminate its Black population ) , and the Worldwar series , in which aliens invaded Earth during World War II .