The international migration and settlement of Koreans began in 1860 and there are now about 6.8 million overseas Koreans in 170 countries. Each wave of Korean migration was driven by different historical factors in the homeland and the host countries, and hence the motivations and characteristics of Korean immigrants in each period were different. The diverse conditions in and government policies of the host countries also affected the mode of entry and incorporation of Koreans. A contrast is drawn between the 'old' and the 'new' Korean migrations. The former consists of those who migrated to Russia, China, America and Japan from the mid-nineteenth to the early twentieth century. They were from the lower classes, pushed out by poverty, war and oppression in the homeland. Few returned to the homeland but preserved their collective identities and ethnic cultures in their host societies. The new migrants to America, Europe and Latin America since the 1960s, however, come from middle-class backgrounds, are pulled by better opportunities in the host countries, travel freely between the homeland and host countries, and maintain transnational families and communities. Despite these differences, overseas Koreans share common experiences and patterns of immigration, settlement and adaptation.