The planes are faster, the engines are bigger, and the guns are more powerful. In this alternate history, the year is 1937 and the United States is fractured into squabbling nation-states, brought about by the weight of the Great Depression, regional prohibition and mounting isolationism. Giant Zeppelins crisscross the skies carrying both passengers and cargo, and airborne bandits are a constant threat. It is a time of gunship diplomacy and airship piracy, as dastardly villains, beautiful air-privateers and valiant militia forces battle for control of the skies over North America. In Crimson Skies, the transcontinental railroad and the budding highway system are useless because they cross the hostile borders of the nation-states. In an effort to maintain commerce and trade, flight becomes the vital lifeline connecting allied countries. America has fallen in love with the airplane, not the automobile, resulting in an explosion of unusual and exotic aircraft.