The University of Glasgow is a public research university in Glasgow, Scotland. Founded by papal bull in 1451 [O.S. 1450], it is the fourth-oldest university in the English-speaking world and one of Scotland's four ancient universities. Along with the universities of St Andrews, Aberdeen, and Edinburgh, the university was part of the Scottish Enlightenment during the 18th century. Glasgow is the largest university in Scotland by total enrolment and, with over 15,900 postgraduates, the fifth-largest in the United Kingdom by postgraduate enrolment.