This thesis contains three essays on income inequality. The underlying theme is to investigate the relationship of income inequality with political instability, economic growth, and financial development. To this end, the first study aims to explore the relationship of income inequality with political instability. Motivated by the observation that politically unstable countries tend to have wide income gaps, the study explores the possibility that major source of political instability is income inequality, which can be traced back to the history of early development across the globe. Using data for 95 countries, the estimates provide support for the notion that before 1500 CE early development of our ancestors, and after 1500 CE colonizatio...