The evolution of political regimes of resource-rich countries is a highly relevant topic as the debates continue about the likelihood of those countries to democratize. Conventional wisdom dictates that large oil endowment impedes democratic development. However, recent studies found that oil and gas can both contribute to and undermine democracy. At the same time, the subject of how and why a democratic resource-rich country backslides to authoritarianism has not been researched in-depth. This thesis argues that the effect of oil and gas endowment depends on who controls the resources: whether the state controls the industry's operations or the industry is run independently from the state. The theory is tested on two cases, Russia and Venezuela, which experienced both democratization and authoritarian backsliding. With two models (independent and state control of hydrocarbon resources) for each case, we found the dynamic of hydrocarbon industry control impacts regime evolution.