Philip Francis Nowlan 
Armageddon-2419 A.D. 

Philip Francis Nowlan (1888 – February 1, 1940) was an American science fiction author, best known as the creator of Buck Rogers. Nowlan’s novella "Armageddon-2419 A.D." tells about America in the 25th century, conquered by Hans in 2109 AD and only now beginning to rebel. Sometime after World War I, nearly all the European powers joined forces against the United States. Although the US won the war, both sides were devastated by the conflict. Taking advantage of the chaos that followed, the ’Russian Soviets’ (USSR) joined forces with the ’Mongolians’ to take over Europe. The US collapsed economically and stagnated while the ’Mongolians’ turned against the Russians and defeated them as part of their campaign of world conquest. American efforts to avoid war with the ’Mongols’ failed and in 2109 AD, they attacked the US using fleets of airships armed with disintegrator rays. They attacked from the Atlantic and Pacific coasts and down from Canada. After conquering the US and Canada, these ’Airlords of Han’ ruled North America as a province of the world empire from fifteen great cities they established across the continent. They ignored the Americans who were left to fend for themselves in the forests and mountains as their advanced technology prevented the need for slave labor.[1] From time to time, they raid American land "to keep the ’wild’ Americans on the run within the shelter of their forests, and prevent their becoming a menace to the Han civilisation." (Excerpt from Wikipedia)