greatest of which is the Khanate of Ch'in) and dozens of semi-independent petty kingdoms that are easy targets for steam-powered Tenochca slave raids. The Tenochca have coaling stations around the world and their continental lands now stretch from the Ohio River to the northern Andes. North of the Tenochca Empire's American territories are the iron mines and weapons factories of the Hotinosavannah League (the Iroquois) to the east and the Tlingit Confederacy to the west. Africa is home to Zoroastrian Egypt, the rapidly arming southern state of KwaZulu and the Songhay Empire, inheritors of Christianity and Roman civilisation. The "current year" in Ezcalli is 1840. Gernsback Gernsback is a parallel that seems drawn straight from a 1930s science fiction adventure story (it is named for the editor Hugo Gernsback, founder of Amazing Stories in which many such tales appeared). Its point of divergence is the marriage of Nikola Tesla to Anne Morgan, daughter of banker and financier J. P. Morgan. In our history the pair were friends, but Tesla died penniless; in Gernsback, their marriage stabilized Tesla, whose inventions went on to revolutionize the world, especially his perfection of a technique for broadcasting electrical power wirelessly. Tesla's brother-in-law J. P. Morgan, Jr. and his companies became instrumental in helping the world's economies recover from the ensuing stock market crash. German and American influence was crucial to the success of the League of Nations in Gernsback; when atomic power was developed in the late 1930s, its World Science Council was placed in charge of nuclear research. Joseph Stalin's Soviet Union saw the potential of atomic energy as a weapon, but the League of Nations sought to forestall the misuse of knowledge in this manner by invading in 1951. The "current year" in Gernsback is 1965; the League of Nations dominates a world which is economically dominated by the World Science Council and socially frozen (especially in matters of race and gender) in the 1930s. The appeal of Gernsback as a setting is less in its alternative history than in its alternative science and retro-futuristic style; its technological development followed a completely different path in the 20th century than did our world (flying cars are ubiquitous, but the transistor has yet to be developed). Publication history GURPS Alternate Earths was published by Steve Jackson Games in 1996, and written by Kenneth Hite, Craig Neumeier and Michael S. Schiffer. A sequel was published