How, why and under what conditions do new racial categories form? This dissertation examines the construction of South and Southeast Asian migrants (tongnama) as a new racial category in South Korea: a country in a continent long neglected within studies of race. Through ethnographic research on foreign migrant workers and marriage immigrants in South Korea, it was discovered that a new racial category has emerged. My findings show that several elements contribute to the racial formation of tongnama migrants: the Korean State, Korean culture, gender and patriarchy, and the Korean labour market. To be specific, exploitative capitalist practices in the Korean labour market and gendered recruitment of foreign brides shape and reshape South Koreans’ understanding of this new racial category. At the same time, the racial formation of South and Southeast Asian migrants emerges out of a need by Koreans to understand their country’s position within contemporary international migration flows.