This chapter traces the physical movement of Muslims to Britain. Muslims came to Britain mainly—though not only—from South Asia, and they settled in certain cities and neighborhoods. Although Muslims living in Britain today trace their origins to many parts of the world, the majority have roots in former British India, and mainly in today's Pakistan and Bangladesh. Furthermore, within those two countries, a small number of districts have contributed in strikingly disproportionate numbers to the Muslim population of Britain. The concentrations began with historical accident but, once in place, reproduced themselves through practices of “chain migration,” whereby one generation of immigrants pulled another after it. The results are concentrations of closely related people in certain British neighborhoods. Many of these new residents of Britain have sought to maintain their ties to the homeland through marriage and through forms of economic cooperation. These practices reinforce ties of shared ethnic and religious community within certain British neighborhoods.