The Home Army (, abbreviated AK; ) was the dominant resistance movement in German-occupied Poland during World War II. The Home Army was formed in February 1942 from the earlier Armed Resistance ("Związek Walki Zbrojnej") established in the aftermath of the German and Soviet invasions in September 1939. Over the next two years, the Home Army absorbed most of the other Polish underground forces. Its allegiance was to the Polish government-in-exile in London, and it constituted the armed wing of what came to be known as the Polish Underground State.