Liverpool is a city in Merseyside, England, on the eastern side of the Mersey Estuary. A borough from 1207 and a city from 1880, in 2011 the city proper had a population of 466,415 and a metropolitan area population of 2,241,000. The city is within the historic county of Lancashire. Its urbanisation and expansion were largely brought about by its status as a major port, which included its participation in the Atlantic slave trade. Liverpool was the port of registry of the ocean liner RMS Titanic, and many other Cunard and White Star ocean liners such as the RMS Lusitania, Queen Mary, and Olympic.