This stone slab forned the lintel from the top of a doorway. It was found at Nineveh by the Assyriologist George Smith in 1874. Although he discovered it in the area of a palace of the Late Assyrian king Sennacherib (704-681 BC), it is clearly late Parthian in date. Creatures comparable to the two winged dragons sometimes appear on the belts of stone statues of the early 3rd century AD from the site of Hatra in northern Mesopotamia, and identical sculptures have also been found at this site. The Parthians were originally a nomadic Iranian tribe. They rose to power around 238 BC when they seized control of the district of Parthia, east of the Caspian Sea. By 141 BC Mithradates I had gained control of Seleucia-on-the-Tigris and possibly established Ctesiphon on the opposite bank of the river. The Euphrates was soon the Parthian frontier with Rome, but their control of the Silk Route brought them great wealth as caravan cities like Hatra, Dura Europos on the Euphrates and Palmyra in the Syrian Desert passed the trade between the Mediterranean and the Han Dynasty of China. This lintel proves that there was also an important settlement of this period the site of the old Assyrian capital of Nineveh which controlled a strategic part of the River Tigris. Other finds of this period from Nineveh include gold face-masks and jewellery found in graves, local and imported Roman pottery, and an inscribed statue of Hercules.