Only 17 months after Hitler announced publicly the rearmament program, the Army reached its projected goal of 36 divisions. During the autumn of 1937, two more corps were formed. In 1938, four additional corps were formed with the inclusion of the five divisions of the Austrian Army after the Anschluss in March. During the period of its expansion by Adolf Hitler, the German Army continued to develop concepts pioneered during World War I, combining ground (Heer) and air (Luftwaffe) assets into combined arms teams. Coupled with operational and tactical methods such as encirclements and the "battle of annihilation", the German military managed quick victories in the two initial years of World War II, prompting the use of the word Blitzkrieg (literally lightning war, meaning lightning-fast war