Many British cities and merchants benefited greatly from the Atlantic slave trade. Bristol, London, Glasgow, Manchester, and Liverpool saw economic growth and development due to slavery. Slave ships left from ports in these cities, creating jobs in dockyards. Merchants grew wealthy trading slaves or goods made by slaves, investing profits into buildings and industries. The slave trade financed sectors like sugar refining in Bristol, banking and shipping in London, cloth mills in Manchester dependent on slave-grown cotton, and shipbuilding and warehouses in Liverpool, the main British port for slave ships. Individual merchants also amassed fortunes, like Thomas Leyland of Liverpool who fiercely opposed abolishing slavery.