The 13th century was the century which lasted from January 1, 1201 (represented by the Roman numerals MCCI) through December 31, 1300 (MCCC) in accordance with the Julian calendar.

The Mongol Empire was founded by Genghis Khan, which stretched from Eastern Asia to Eastern Europe. The conquests of Hulagu Khan and other Mongol invasions changed the course of the Muslim world, most notably the Siege of Baghdad (1258) and the destruction of the House of Wisdom. Other Muslim powers such as the Mali Empire and Delhi Sultanate conquered large parts of West Africa and the Indian subcontinent, while Buddhism witnessed a decline through the conquest led by Bakhtiyar Khilji. The earliest Islamic states in Southeast Asia formed during this century, most notably Samudera Pasai. The Kingdoms of Sukhothai and Hanthawaddy would emerge and go on to dominate their surrounding territories.

Europe entered the apex of the High Middle Ages, characterized by rapid legal, cultural, and religious evolution as well as economic dynamism. Crusades after the fourth, while mostly unsuccessful in rechristianizing the Holy Land, inspired the desire to expel Muslim presence from Europe that drove the Reconquista and solidified a sense of Christendom. To the north, the Teutonic Order Christianized and gained dominance of Prussia, Estonia, and Livonia. Inspired by new translations into Latin of classical works preserved in the Islamic World for over a thousand years, Thomas Aquinas developed Scholasticism, which dominated the curricula of the new universities.