Assyrian inscriptions of Shalmaneser I (c. 1274 BCE) first mention Uruartri as one of the states of Nairi, a loose confederation of small kingdoms and tribal states in the Armenian Highlands in the thirteenth to eleventh centuries BCE which he conquered. Uruartri itself was in the region around Lake Van. The Nairi states were repeatedly subjected to further attacks and invasions by the Middle and Neo-Assyrian Empires, which lay to the south in Upper Mesopotamia (“the Jazirah”) and northern Syria, especially under Tukulti-Ninurta I (c. 1240 BCE), Tiglath-Pileser I (c. 1100 BCE), Ashur-bel-kala (c. 1070 BCE), Adad-nirari II (c. 900 BCE), Tukulti-Ninurta II (c. 890 BCE), and Ashurnasirpal II (883–859 BC).
Urartu reemerged in Assyrian language inscriptions in the ninth century BCE as a powerful northern rival to the Neo-Assyrian Empire. The Nairi states and tribes became a unified kingdom under King Arame of Urartu (c. 860–843 BCE), whose capitals, first at Sugunia and then at Arzashkun, were captured by the Assyrians under the Neo-Assyrian emperor Shalmaneser III.
Urartologist Paul Zimansky speculated that the Urartians, or at least their ruling family after Arame, may have emigrated northwest into the Lake Van region from their religious capital of Musasir.
According to Zimansky, the Urartian ruling class were few in number and governed over an ethnically, culturally, and linguistically diverse population. Zimansky went so far as to suggest that the kings of Urartu might have come from various ethnic backgrounds themselves.

Growth
Assyria fell into a period of temporary stagnation for decades during the first half of the 8th century BC, which had aided Urartu’s growth. Within a short time, it became one of the largest and most powerful states in the Near East.
Sarduri I (c. 832–820 BCE), the son of Lutipri, established a new dynasty and successfully resisted Assyrian attacks from the south led by Shalmaneser III, consolidated the military power of the state, and moved the capital to Tushpa (modern Van, Turkey on the shore of Lake Van). His son, Ispuini (c. 820–800 BCE) annexed the neighbouring state of Musasir, which became an important religious centre of the Urartian Kingdom, and introduced the cult of Ḫaldi.
Ispuini was also the first Urartian king to write in the Urartian language (previous kings left records written in Akkadian). He made his son Sarduri II viceroy. After conquering Musasir, Ispuini was in turn attacked by Shamshi-Adad V. His co-regent and subsequent successor, Menua (c. 800–785 BCE) also enlarged the kingdom greatly and left inscriptions over a wide area. During Ispuini’s and Menua’s joint rule, they shifted from referring to their territory as Nairi, instead opting for Bianili.
Urartu reached the highest point of its military might under Menua’s son Argishti I (c. 785–760 BCE), becoming one of the most powerful kingdoms of ancient Near East. Argishti I added more territories along the Aras and Lake Sevan, and frustrated Shalmaneser IV’s campaigns against him. Argishti also founded several new cities, most notably Erebuni Fortress in 782 BCE. 6600 captured slaves worked on the construction of the new city.
At its height, the Urartu kingdom stretched north beyond the Aras and Lake Sevan, encompassing present-day Armenia and even the southern part of present-day Georgia almost to the shores of the Black Sea; west to the sources of the Euphrates; east to present-day Tabriz, Lake Urmia, and beyond; and south to the sources of the Tigris.
Tiglath-Pileser III of Assyria conquered Urartu in the first year of his reign (745 BCE). There the Assyrians found horsemen and horses, tamed as colts for riding, that was unequalled in the south, where they were harnessed to Assyrian war-chariots.

Decline and recuperation
In 714 BC, the Urartian kingdom suffered heavily from Cimmerian raids and the campaigns of Sargon II. The main temple at Mushashir was sacked, and the Urartian king Rusa I was crushingly defeated by Sargon II at Lake Urmia. He subsequently committed suicide in shame.
Rusa’s son Argishti II (714–685 BC) restored Urartu’s position against the Cimmerians, however, it was no longer a threat to Assyria and peace was made with the new king of Assyria Sennacherib in 705 BC. This, in turn, helped Urartu enter a long period of development and prosperity, which continued through the reign of Argishti’s son Rusa II (685–645 BC).
After Rusa II, however, Urartu grew weaker under constant attacks from Cimmerian and Scythian invaders. As a result, it became dependent on Assyria, as evidenced by Rusa II’s son Sarduri III (645–635 BC) referring to the Assyrian king Ashurbanipal as his “father”.

Fall
According to Urartian epigraphy, Sarduri III was followed by three kings—Erimena (635–620 BC), his son Rusa III (620–609 BC), and the latter’s son Rusa IV (609–590 or 585 BC). Late during the 7th century BC (during or after Sarduri III’s reign), Urartu was invaded by Scythians and their allies—the Medes. In 612 BC, the Median king Cyaxares the Great together with Nabopolassar of Babylon and the Scythians conquered Assyria after it had been irreversibly weakened by civil war. The Medes then took over the Urartian capital of Van in 590 BC, effectively ending the sovereignty of Urartu. Many Urartian ruins of the period show evidence of destruction by fire.

Appearance of Armenia
The Kingdom of Van was destroyed in 590 BC and by the late 6th century, the Satrapy of Armenia had replaced it. Little is known of what happened to the region between the fall of the Kingdom of Van and the appearance of the Satrapy of Armenia. According to historian Touraj Daryaee, during the Armenian rebellion against the Persian king Darius I in 521 BC, some of the personal and topographic names attested in connection with Armenia or Armenians were of Urartian origin, suggesting that Urartian elements persisted within Armenia after its fall. In the Behistun Inscription (c. 522 BC), as well as the XV Inscription (c. 486–465 BC), refer to Armenia and Armenians as synonyms of Urartu and Urartians.
The toponym Urartu did not disappear, however, as the name of the province of Ayrarat in the centre of the Kingdom of Armenia is believed to be its continuum.
As the Armenian identity developed in the region, the memory of Urartu faded and disappeared. Parts of its history passed down as popular stories and were preserved in Armenia, as written by Movses Khorenatsi in the form of garbled legends in his 5th-century book History of Armenia, where he speaks of a first Armenian Kingdom in Van which fought wars against the Assyrians. Khorenatsi’s stories of these wars with Assyria would help in the rediscovery of Urartu.
According to Herodotus, the Alarodians (Alarodioi), presumably a variation of the name Urartian/Araratian, were part of the 18th Satrapy of the Achaemenid Empire and formed a special contingent in the grand army of Xerxes I. According to this theory, the Urartians of the 18th Satrapy were subsequently absorbed into the Armenian nation. Modern historians, however, have cast doubt on the Alarodian connection to the Urartians as the latter is never recorded as having applied an endonym related to “Ararat” to themselves.
In a study published in 2017, the complete mitochondrial genomes of 4 ancient skeletons from Urartu were analyzed alongside other ancient populations found in modern-day Armenia and Artsakh spanning 7,800 years. The study shows that modern-day Armenians are the people who have the least genetic distance from those ancient skeletons.