After Deioces's death in 674 BCE, his son Phraortes took the reins of the nascent Median kingdom and ruled over the land for 22 years. Phraortes, who in some sources was introduced as the ruler and judge of a city, succeeded his father as the head of the Median tribal confederation. Unlike Deioces, who focused more on justice and internal stabilization, Phraortes sought to expand and consolidate Media's power against foreign enemies, especially Assyria. His primary goal was to completely free himself from the Assyrian yoke and extend Median territory westward.
Immediately upon coming to power, Phraortes concentrated on military aspects and increasing strength. By uniting the scattered Median tribes and attracting other forces opposed to Assyria, including the Scythians and Persians, he formed a disciplined and powerful army. These alliances not only indicated the growing influence of the Medes in the region but also enabled Phraortes to confront the oppressive Assyrian power more seriously, relying on his growing military might, and to nurture the Medes' long-held aspiration for complete independence.
With increasing military power and the incitement of a desire for revenge against Assyria, Phraortes decided to attack Assyrian territory. He dispatched his troops towards Nineveh, the formidable Assyrian capital. This campaign, despite great audacity and courage, was not successful. Phraortes, due to his inexperience in major battles and the emergence of internal disputes with his allies, especially the Scythians, could not withstand the powerful and seasoned Assyrian army.
In the midst of the battle, the Scythians, who were themselves a warlike and equestrian people, at critical moments either separated from Phraortes's army and joined the Assyrians or, according to some accounts, attacked Median territory, which led to weakness and disarray in the Median front. This action was the result of incomplete cohesion and deeper disagreements among Phraortes's allies, which the Median kingdom had not yet been able to fully overcome. Phraortes's army was crushed, and he was killed on the battlefield in 653 BCE.
This defeat and the death of Phraortes were very heavy blows for the nascent Median kingdom and led to devastating consequences. After this victory, the Scythians dominated parts of Media and its surrounding regions, and this dominance lasted for about 28 years. This period, known as the "Scythian domination," brought many challenges for the Medes; many areas under Median influence were plundered and ravaged, and the relative order and security established by Deioces became disrupted and chaotic.
After this difficult period, Cyaxares (known as "Kyaxares" in ancient sources, and some historians consider him to be Deioces II or the son of Phraortes) took leadership of Media. He assumed power in 653 BCE, at the height of Scythian dominance in the region and when the Medes were weakened. Cyaxares, with great wisdom and patience, set about rebuilding Median forces and reorganizing the tribes, seeking an opportunity to free himself from Scythian rule and also to take revenge on the Assyrians.
Cyaxares clearly understood that to confront two powerful enemies (the Scythians and Assyria), he needed to proceed with caution and planning. He first focused on rebuilding the Median army, establishing it on stronger foundations. Then, with his diplomatic skill, he managed to ally with the Mannaeans and remnants of Scythian tribes who had a long-standing enmity with Assyria, against the Assyrians. This new alliance indicated a shift in the balance of power in the region and gave the Medes a fresh opportunity to revive their power and influence.
Finally, Cyaxares died in 625 BCE, having laid the necessary foundations for the future greatness of the Median kingdom. He managed to rescue the Medes from their period of weakness and Scythian domination, guiding them towards a new era of power and influence. His legacy was a rebuilt army and a network of alliances, which his son, Cyaxares II (Huakhshatra), utilized to bring Media to its historical zenith of power.