 Constantinople jostled with other major historical cities, such as Baghdad, Chang'an, Kaifeng and Merv for the position of world's most populous city until the 12th century.It never returned to being the world's largest, but remained Europe's largest city from 1500 to 1750, when it was surpassed by London.The Turkish Statistical Institute estimates that the population of Istanbul Metropolitan Municipality was 14,377,019 at the end of 2014, hosting of the country's population.