Baghdad (pop. 4,000,000), capital and largest city of Iraq, on both banks of the Tigris River, at a point where the Tigris is only 25 mi (40 km) from the Euphrates. Founded 762 A.D., the city became the center of Arab and Muslim civilization during its golden age, in the 9th and 10th centuries. In 1258 the city was sacked by the Mongols, and in 1638 it became part of the Ottoman Empire. In 1921 it became the capital of the newly formed kingdom of Iraq. After World War II Baghdad developed into a modern metropolis. The city is a shipping and industrial center and has an international airport. During the Gulf War the city was damaged by allied bombing.