Yaqut Al- Hamawi (from Hamah, Syria, 1179–1229 AD, 574–626 AH) was an Arab geographer of Greek origins. Born in Byzantium (the ancient Greek city also known as Constantinople, or present-day Istanbul), he was captured in war and enslaved. He was purchased by a Baghdad merchant, who gave him a good education and ultimately freed him. Yaqut traveled extensively in Egypt, Syria, Iraq, and Persia (present-day Iran). His Mu'jam al-Buldan (Dictionary of countries) is a vast geographical encyclopedia, which summarizes nearly all medieval knowledge of the globe. The information in the dictionary is wide ranging, and includes archaeology, ethnography, history, anthropology, natural sciences, geography, and the coordinates of places listed. The work gives the various names by which towns and cities were known and describes their monuments and wealth, history, population, and leading figures. The book is a primary source widely used in Arabic scholarship.