Black serpentine scaraboid stamp seal, Assyria or Mesopotamia, 8th-7th century BC. Assyria was a Semitic Akkadian kingdom, extant as a nation state from the 25th or 24th century BC until 605 BC. Assyria was centered on the Upper Tigris river, in northern Mesopotamia. The Assyrians came to rule powerful empires a number of times through history. As part of the greater Mesopotamian civilization, Assyria was at its height a highly advanced nation for its time in terms of architecture, engineering, agriculture, economics, civil service, mathematics, medicine, literature, military technology, law, astronomy and libraries/record keeping. The stamp seal is a carved object, usually stone, first made in the 4th millennium BC, and probably earlier. They were used to impress their picture or inscription into soft, prepared clay. The device of the seal has seldom survived through time; it is usually only their impressions.