Coolie is a historical term for manual labourers or slaves from Asia, particularly China, India, and the Philippines during the nineteenth century and early twentieth century. This photograph was taken in Tien-Tsin, China. Situated in northern China, now called Tianjin, it is one of the five national central cities of the People's Republic of China. At the end of the first part of the Second Opium War (1856 to 1860) the Treaties of Tianjin were signed, which opened Tianjin to foreign trade. The treaties were ratified by the Emperor of China in 1860, and Tianjin was formally opened to trading with Great Britain and France, and consequently the outside world.