This dissertation investigates racial, ethnic, and gender issues mainly in developing countries. The first two chapters examine the relationship between mass-media and identity, and the third chapter examines the labor market formation and gender wage difference in an emerging modern industry.

The first chapter, titled, ``Building the Rainbow Nation through Mass Media: Television, Cultural Diversity, and National Unity in post-Apartheid South Africa'' examines whether national mass-media promotes cultural diversity, while preserving national unity. “Rainbow Nation” was a national slogan to make cultural differences a source of strength in South Africa. Television broadcasts in South Africa promote both cultural diversity and national unity, aligning with that national slogan. I investigate the effects of television broadcasts on two outcomes—language choices in elementary schools, which are associated with cultural identities, and voting shares of political parties that espouse opposite views on national unity. I digitize locations and features of television transmitters, leverage topographical and time variations that determine television broadcast coverage over time, and, using a difference-in-differences approach, estimate the effects of broadcasts on the two outcomes listed above. I find that exposure to television broadcasts increases the use of native languages in schools, which contributes to cultural diversity. Such exposure also increases voting shares for the political parties that promote national unity.

The second chapter, ``Radio and Racism during Apartheid'', investigates the impacts of radio programs, which opposed racial segregation policies, on amplification of racism in South Africa during Apartheid. During Apartheid, radio broadcasts were highly censored, and information against racial segregation, such as international sanctions and riots in Black townships were not broadcasted. However, due to political reasons, people could listen to uncensored radio in a part of the country. I digitize locations of radio transmitters and estimate its impacts on voting behaviors which were highly associated with preferences on segregation policies for the White population. Difference-in-differences analyses show that exposure to anti-Apartheid radio reduced supports for a right wing-party which promoted racial segregation and increased supports for a left-wing party which opposed the segregation.

The third chapter titled ``Labor Market Evolution in an Emerging Industry: Japanese Cotton Spinning Industry before 1900'' is a coauthored paper with Serguey Braguinsky. We utilize an unusually rich historical data set on firms, establishments, workers and wages in the Japanese cotton spinning industry in late 19th to explicitly link the evolution of the industry to labor market outcomes in the long run. In the early periods, firms recruited workers with low wages that resembles Harris and Todaro's dual economy model. We then show that soon after experiencing new entries, competitions to acquire skilled workers changed the nature of labor market toward competition, and wages for both gender increased.