Leeds is a city in West Yorkshire, England. In 2011, it had an estimated population of 757,700, making it the third largest city in the United Kingdom.Historically in the West Riding of Yorkshire, the history of Leeds can be traced to the 5th century when the Kingdom of Elmet was covered by the forest of "Loidis", the origin of the name Leeds. The name has been applied to many administrative entities over the centuries. It changed from being the appellation of a small manorial borough, in the 13th century, through several incarnations, to being the name attached to the present metropolitan borough. In the 17th and 18th centuries Leeds became a major centre for the production and trading of wool. Then, during the Industrial Revolution, Leeds developed into a major mill town; wool was the dominant industry but flax, engineering, iron foundries, printing, and other industries were important. From being a compact market town in the valley of the River Aire in the 16th century Leeds expanded and absorbed the surrounding villages to become a populous urban centre by the mid-20th century.Today Leeds is ranked as a gamma world city by the Globalization and World Cities Research Network; and is considered the cultural, financial and commercial heart of the West Yorkshire Urban Area. Leeds is served by five universities, and has one of the largest student populations in the country with over 250,000 students. and has the country's fourth largest urban economy. After London, Leeds is the largest legal centre in the UK, and in 2011 its financial and insurance services industry was worth £2.1 billion, the 5th largest in the UK, with over 30 national and international banks located in the city. It is the leading UK city for telephone delivered banking and related financial services, with over 30 call centres employing around 20,000 people.