The Indo-Saka or Indo-Scythians are commonly thought to have been a branch of Sakas (Scythians), who migrated from southern Siberia into Bactria, Sogdiana, Arachosia, Gandhara, Kashmir, Punjab, Gujarat, Maharashtra and Rajasthan, from the middle of the 2nd century BCE to the 4th century CE.
The first Saka king in Pakistan and India was Maues or Moga who established Saka power in Gandhara (Pakistan) and gradually extended supremacy over north-western India. Indo-Scythian rule in India ended with the last Western Satrap Rudrasimha III in 395 CE. In the 2nd century BCE, a fresh nomadic movement started among the Central Asian tribes, producing lasting effects on the history of Rome in Europe and Bactria, Kabul, Parthia and India in the east. Recorded in the annals of the Han dynasty and other Chinese records, this great tribal movement began after the Yuezhi tribe was defeated by the Xiongnu, fleeing westwards after their defeat and creating a domino effect as they displaced other central Asian tribes in their path. They thus displaced the Sakas, who migrated south into Ferghana and Sogdiana. Sometime after 155 BCE, the Yuezhi were again defeated by an alliance of the Wusun and the Xiongnu, and were forced to move south, again displacing the Scythians, who migrated south towards Bactria, and south-west towards Parthia and Afghanistan.
The Sakas seem to have entered the territory of the Greco-Bactrian Kingdom around 145 BCE, where they burnt to the ground the Greek city of Alexandria on the Oxus. The Yuezhi remained in Sogdiana on the northern bank of the Oxus, but they became suzerains of the Sakas in Bactrian territory, as described by the Chinese ambassador Zhang Qian who visited the region around 126 BCE. In Parthia, between 138–124 BCE, the Sakas tribes of the Massagetae and Sacaraucae came into conflict with the Parthian Empire, winning several battles, and killing successively King Phraates II and King Artabanus I. The Parthian king Mithridates II finally retook control of Central Asia, first by defeating the Yuezhi in Sogdiana in 115 BCE, and then defeating the Scythians in Parthia and Seistan around 100 BCE. After their defeat, the Yuezhi tribes migrated into Bactria, which they were to control for several centuries, and from which they later conquered northern India to found the Kushan Empire. The Sakas settled in areas of southern Afghanistan, still called after them Sakastan. From there, they progressively expanded into the Indian subcontinent, where they established various kingdoms, and where they are known as "Indo-Scythians".
The first Indo-Scythian kingdom in the Indian subcontinent occupied the southern part of what is now modern day Pakistan (which they accessed from southern Afghanistan), in the areas from Abiria (Sindh) to Surastrene (Gujarat), from around 110 to 80 BCE. They progressively further moved north into Indo-Greek territory until the conquests of Maues, c 80 BCE. In the southeast, the Indo-Scythians invaded the area of Ujjain, but were subsequently repelled in 57 BCE by the Malwa king Vikramaditya. To commemorate the event Vikramaditya established the Vikrama era, a specific Indian calendar starting in 57 BCE. More than a century later, in 78 CE the Sakas would again invade Ujjain and establish the Saka era, marking the beginning of the long-lived Saka Western Satraps kingdom.
In central India, the Indo-Scythians conquered the area of Mathura over Indian kings around 60 BCE. Some of their satraps were Hagamasha and Hagana, who were in turn followed by the Saca Great Satrap Rajuvula. After the death of Azes, the rule of the Indo-Scythians in northwestern India was shattered with the rise of the Indo-Parthian ruler Gondophares in the last years of the 1st century BCE. For the following decades, a number of minor Scythian leaders maintained themselves in local strongholds on the fringes of the loosely assembled Indo-Parthian empire,some of them paying formal allegiance to Gondophares I and his successors. During the latter part of the 1st century CE, the Indo-Parthian overlordship was gradually replaced with that of the Kushans, one of the five tribes of the Yuezhi who had lived in Bactria for more than a century, and were now expanding into India to create a Kushan Empire. The Kushans ultimately regained northwestern India from around 75 CE, and the area of Mathura from around 100 CE, where they were to prosper for several centuries.
The invasion of India by Scythian tribes from Central Asia, often referred to as the Indo-Scythian invasion, played a significant part in the history of South Asia as well as nearby countries. In fact, the Indo-Scythian war is just one chapter in the events triggered by the nomadic flight of Central Asians from conflict with Chinese tribes which had lasting effects on Bactria, Kabol, Parthia and India as well as far off Rome in the west.
c. 200 BCE - c. 100 BCE
c. 110 BCEArachosia lost to the first Indo-Saka kingdom.