The Global Expansion of Primary Education is an unpublished short paper. In 1830, near-universal primary education was limited to a few states in the United States, and the great majority of the World’s children received no formal education at all. By 1870, somewhere between 12 and 23 percent of the World’s children aged 5-14 were enrolled in a school, and by 1950 this figure had increased to 47 percent. By 2002, global net primary enrollment was around 87 percent, with a gross enrollment ratio of around 100 percent. For countries in Western Europe and Western offshoots including the US and Canada, the period of rapid growth began as early as the 1800s, while for much of the rest of the World, it would take at least another 100-150 years to see the takeoff towards universal primary education. This paper discusses the timing and speed of the transition around the World and discusses the causal mechanisms behind the growth to global ubiquity of basic education.