Friedrich Ratzel (Karlsruhe, 1844 - † Ammerland, 1904), was German geographer. He served as professor of geography at the universities of Leipzig and Munich._x000D_
Ratzel made several trips to Europe and America from 1869 to 1875. Although not founded geopolitics (the first to speak of this term was Rudolf Kjellén) was one of its greatest exponents. Influenced by the ideas of Darwin and nineteenth-century deterministic thesis, reflected on the relationship between geographic area and population, and tried to relate the history of the world with natural laws. Similarly, played an important role in evolutionary anthropology, opposed to the idea that people will need to spread their cultural traits beyond their original environment and, in turn, contacts with other peoples for development._x000D_

Ratzel facing the evolution to diffusionism, completing the motor trade as progreso.Más later created the concept of living space (Lebensraum). Considered the state (once passed its early stages) as an organism and living space that was needed to ensure the survival of a state against others through the fight or competition._x000D_
The theory of Ratzel's living space was used in Germany for the Third Reich to support its expansionist policies. The German defeat in World War II for a time discredited geopolitical has regained interest._x000D_
The most important works were anthropogeography Ratzel (1891) and Political Geography (1897).