Mahmud II was the sultan of the Ottoman Empire from 1808 until his death in 1839. Often described as the "Peter the Great of Turkey", Mahmud instituted extensive administrative, military, and fiscal reforms. His disbandment of the conservative Janissary Corps removed a major obstacle to his and his successors' reforms in the Empire, creating the foundations of the subsequent Tanzimat era. Mahmud's reign was also marked by further Ottoman military defeats and loss of territory as a result of nationalist uprisings and European intervention.