In 745 BC, the king of Assyria Tiglath-Pileser III gave a beginning to a conflict between his state and Kingdom of Van. It was a part of his policy of reforming Assyria and strengthening its positions in Western Asia.
In 735 BC, Tiglath-Pileser III assaulted the capital of Kingdom of VanTosp, but was unable to capture it. That offensive significantly loosened the unity of Kingdom of Van. Moreover, Tiglath-Pileser’s campaign allowed Assyria to start the process of regaining its political positions.
After the assault, the situation in Kingdom of Van became extremely complicated. In this conditions, the son of Sarduri II Rusa I acceded the throne. The successful reforms inside Assyria gave a rise to pro-Assyrian movements inside the provinces of Kingdom of Van. Rusa I had to reorganize the governmental and military systems of his kingdom.
His first step was establishing local governmental bodies in the provinces of Kingdom of Van. As for the army, separate units of cavalry were created. Besides, the process of mobilization was altered and provincial troops were formed. Rusa I organized crusades to counteract the pro-Assyrian forces inside the country. He conquered 23 provinces near Lake Sevan and included them into Kingdom of Van’s governmental system.
In the region of Sevan, two fortresses were renovated and renamed Khaldi and Teisheba. Then, Rusa I started to concentrate his efforts around the city of Musasir-Ardini near the Lake Urmia. He managed to overthrow its Assyrian ruler and appoint a new one. The city became the location of the shrine of Khaldi, one of the three chief deities of Kingdom of Van.
After restoring his positions in Aghdznik, Rusa I clashed with the king of Assyria Sargon II and prevented his advancement towards Kingdom of Van in 719 BC. Rusa I captured territories to the east of Kingdom of Van up to the Caspian Sea. In 716 BC, the conflict between Kingdom of Van and Assyria became a war. The situation was complicated by the raids of Cimmerian nomads, resulting in the weakening of Rusa’s positions.
In 714 BC, the troops of Sargon II attacked Kingdom of Van. Although his assault was unsuccessful, the Assyrian army conquered Musasir-Ardini and plundered the main temple of Khaldi. Even local Assyrians had worshiped Khaldi, so the actions of Assyrian troops were a sacrilege and disrespect towards the doctrines of their compatriots.
According to the notes of Sargon II, Rusa I has yet been the king of Kingdom of Van in 713 BC, when he managed to reclaim Musasir with the movements against Assyria in Asia Minor in the background.
During the conflict with Kingdom of Van in 743-713 BC, Assyria has managed to regain its positions in Western Asia and become one of the most powerful states of the region.