After Alexander the Great, the greed seleukidan dynasty of Persia held on to the trans-Indus region. After seleukos Nikator was defeated by Chanragupta Maurya in 303 B.C. the trans-Indus region was transferred to the Mauryas. In mid third century B.C. the seleukidan rule was ended by two peoples. In Iran the parthiar became independent and their sassanians in 226 A.D. In like manner the greeks of Bactria rose in revolt under the leadership of Diodotus. These Greeks were later known as Indo-Greeks when they gained a foot-hold in the Indian sub-continent.
Bactria situated between the Hindu Kush and the oxus, was a fertile region and it controlled the trade routes from Gandhara to the West. The greek settlement in Bactria began in the 5th century B.C. when Persian emperors settled the Greek exiles in that area.
Bactria figured in history with the revolt of diodotus against Antiochus the seleukidan king. This breakaway of Bactria was recnised by the seleukidans when the grandson of Diodotus, Enthymemes. Was given a seleukidan bride in about 200 B.C.
About the same time the seleukidan king defeated king subhagasena after crossing the Hindu Kush in 206 B.C. This defeat reveals the unguarded nature of northwestern India.
Thus begins the history of Indo-Greeks. The history of the Indo-Greeks is mainly gathered from their coins. This evidence is very often confusion because many kings had identical names.
The most known Indo-Greek was Menander, whose claim rests on the Buddhist treatise the Questions of king Milinda-discussion between menander and the Buddhist philosopher, Nagasena and he ruled the Punjab from C.160 to 140 B.C.
Menander not only stabilized his power but extended his frontiers. His coins are to be found in the region extending from Kabul to Mathura near Delhi. He attempted to conquer the Ganges valley but in vain. Probabley he was defeated by the Sungas.
After menander one Strato ruled. At that time Bactaria was rule by a different group of Bactrians. Probably Mitrhadates – I of Persia annexed the region of Taxila during the third quarter of the second century B.C.
The last known greek kings were hippostratos and Hermaeus, the former defeated by moga and the latter by khadphisus.
The penetration of Indo-Greeks, as well as of sakas pahlavas and Kushana influenced the government, society, religion literature and art of ancient India. The very fact that India absorbed influences of these foreigners speaks for the then youthful nature of Indian civilization.