Urshu, Warsuwa or Urshum was a Hurrian-Amorite city-state in southern Turkey, probably located on the west bank of the Euphrates, and north of Carchemish.
Urshu was a commercial city governed by a Lord (EN). It was an ally of Ebla and appears in the tablets as Ursa'um. Later it was mentioned in the inscriptions of Gudea (r. c.2144–2124 BC according to the Middle chronology) as the city where wood resins were procured. An old Assyrian letter that dates to the 19th century BC mentions a temple of the god Ashur in Urshu.
In the beginning of the 18th century BC, Urshu allied with Yamhad against Yahdun-Lim of Mari. Relations with Assyria were also strained, and men of Urshu were summoned by Yapah-Adad and his Habiru to attack the lands of Shamshi-Adad I of Assyria. The texts of Mari mentions a conflict between Urshu and Carchemish: the tribes of Upra-peans and Ra-beans attacked Urshu through the land of Carchemish, which caused Urshu to attack a contingent of Carchemishean troops and civilians that advanced along the bank of the Euphrates.
Later, Urshu became an economic rival to Yamhad and entered an alliance with Qatna and Shamshi-Adad I to attack Sumu-Epuh of Yamhad (r. c.1810-1780 BC). The death of Shamshi-Adad and the rise of Yarim-Lim I of Yamhad brought an end to this rivalry, as Yamhad was elevated into a Great Kingdom and imposed its direct authority over northern, western and eastern Syria, bringing Urshu under its sphere of influence without annexing it. The Tablets of Mari mention a few kings of Urshu who date to this era, including Shennam and Atru-Sipti, who visited Mari in the 12th year of its king Zimri-Lim.