Complex sentence: The History of Aviation started in issue 1 with the Vietnam War, most of the History of Aviation was taken up with warfare especially World War II starting with the Blitzkreig and ending with the war in the Pacific.
Split into simpler sentences: The History of Aviation started in issue 1 with the Vietnam War. Most of the History of Aviation was taken up with warfare especially World War II starting with the Blitzkreig and ending with the war in the Pacific.