In 1,000,000 B.C. cavewomen were fighting dinosaurs and wearing rabbit-skin lingerie. By 10,000 B.C. teeth were the new rabbit-skins and mammoths were the new dinosaurs, but otherwise very little had changed. In 1492 Chris Columbus discovered America and the Round Earthers enjoyed a certain amount of social acceptance, and in 1941 America was saved from a Japanese invasion by a bunch of idiots. In 1969 it turned out that War was officially a bad thing however by 1984 we had forgotten this and were all in love with Big Brother.
2001 was of course the Dawn of Mankind and this had something to do with malfunctioning computers and black obelisks. Despite, or possibly due to those idiots in 1941, Japan never actually lost World War II and Korea never gained independence - until 2009 when the Korean resistance begins. Luckily in 2010 those monolith-loving aliens are back to sort everything out for humanity, at least until the world ends in 2012 as a direct consequence of the Mayan Calendar-Makers Strike. But it all ends well - by 2046 the world has been rebuilt as a supercity with some really cool trains.