In 1851, the Great Exhibition was held in London. During the exhibition, more than six million people gathered in London, which added more unstable factors to the United Kingdom in a special era of class tension. Maintaining order and stability during the exhibition became one of the major problems that the British government had to deal with. The British police took security such as increasing the number of police, setting up emergency plans and inviting foreign police to assist to maintain the security and stability. The outstanding performance of the British police during the Exhibition vividly displayed their ability to maintain public order.