Complex sentence: During World War II he served in North Africa and France (he spoke fluent French) for military intelligence and set up political and economic intelligence units, while also serving for seven months as an assistant military attaché at the American Embassy in Paris.
Split into simpler sentences: During World War II he served in North Africa and France (he spoke fluent French) for military intelligence setting up political and economic intelligence units. For seven months he also served as an assistant military attaché at the American Embassy in Paris.