The work briefly summarizes, the analysis emerged by studying two particular moments in Mexican history with regards to its energy policies: with principal focus on the years of oil expropriation in 1938 and the promulgation of the Energy Reform of December of 2013 with the addition of exploring how the seek for Foreign Direct Investment (FDI), appears as a factor of international economics that has influenced these processes. Since Enrique Peña Nieto arrived to power, the energy model of the Mexican Republic have experimented its biggest transformations after seventy-five years of protectionism. This last reform took to an end the monopoly in industry of the national oil company Petróleos Mexicanos (PEMEX). México belongs now to the North American Free Trade Agreement, previously non-existent when in the 30s president Lázaro Cardenas Del Rio elicited support of the population to expropriate the oil and gas industry. The purpose of this study is to analyze how historical driving forces on a geopolitical perspective, can influence the process of policy-making on the Mexican energy sector. Oil has been known as the blood of the political and economic system of Mexico. To this end, the thesis relies on Classical Geopolitics that combines the Realist Theory of International relations to explore the historical driving forces affecting the outcome of energy policies. With the classification of the geopolitical drivers, identified adopting the model of analysis of the international system proposed by Mark E. Williams, it is possible to reveal implications on the undergone changes in policymaking, especially on energy and foreign affairs. This work is the product of the insights on the impacts of the oil industry in energy policy making, and the repercussions this activity has on foreign policy.