The earliest known inhabitants of Amman were the Ammonites, a Semitic people who settled in the region around 1200 BC. The Ammonites built a number of fortifications in the area, and the city was known as Rabbath Ammon during this period. The city was conquered by the Babylonians in 600 BC, and was later ruled by the Persians, Greeks, and Romans. In the 4th century AD, Amman was conquered by the Byzantines, who renamed it Philadelphia.
In the 7th century, the city was conquered by the Umayyad Caliphate, and it became an important center of Islamic culture. The city was renamed Amman, and it flourished under Umayyad rule. In the 11th century, Amman was conquered by the Crusaders, who built a number of fortifications in the area. The city was then ruled by the Ayyubid dynasty, the Mamluks, and the Ottomans.
In the 19th century, Amman became part of the Ottoman Empire. During this period, the city was modernized, and the first railway line was built in 1892. In 1921, Amman became the capital of the newly created Emirate of Transjordan, which later became the Hashemite Kingdom of Jordan.
Today, Amman is a bustling and modern city, with a population of over four million people. The city is home to a number of important archaeological sites, including the Citadel of Amman and the Roman Theatre. Amman is also a popular tourist destination, with many attractions such as the Jordan Museum, the Roman Amphitheatre, and the King Abdullah Mosque.