The global production of steel in a year is in the range of several millions of tonnes due to its essential function in industries such as automotive, manufacturing, and construction among others. However, a major challenge faced by the steel industry in the development of new steel grades is the inability to predict surface behaviour, such as the concentration profiles of alloying elements like manganese. This is due to the inability to predict the oxidation behaviour during the processing of steel. In order to solve this challenge, experimental data regarding oxidation on a short timescale is required which is not yet well-addressed in literature. Some of this data required will be generated in this research project via the experimental investigation of the oxidation of Fe-Mn binary alloys at high temperature. In this project, the oxidation experiments are performed on Fe-Mn alloys having a manganese composition ranging from 0.5-7% Mn in temperatures ranging from 1000-1150 degrees Celsius and oxygen partial pressures ranging from 0.1-0.3 atm. The oxidation behaviour is studied using thermogravimetric analysis and the oxide layer is then characterised using X-ray diffraction. The in-situ evolution of oxide structure is observed using high temperature X-ray diffraction, and finally the rate determining mechanism for the oxidation of Fe-Mn alloys at high temperature is identified.