controlled by the Kushans under Kanishka, with him conquering Punjab. However in the early 3rd century BCE after his death, a union formed between the republics to expel the Kushans, resulting in a Kushan defeat and them being pushed out of Eastern Punjab, as stated by the historian Anant Sadashiv Altekar. This can also be confirmed through their coinage inscription stating 'Yaudheyanam jayamantra daramanam' boasting their military victory. A century later, according to the Allahabad pillar inscription, the republics would become tributaries of the Guptas however this would be done without a fight and according to Upinder Singh there is no specific mention of them providing troops, indicating loose ties. This period ultimately saw the disappearance of the republics. Mauryan empire (c. 320–180 BCE) Chandragupta Maurya, with the aid of Kautilya, had established his empire around 320 B.C. The early life of Chandragupta Maurya is not clear. Kautilya enrolled the young Chandragupta in the university at Taxila to educate him in the arts, sciences, logic, mathematics, warfare, and administration. Megasthenes' account, as it has survived in Greek texts that quote him, states that Alexander the Great and Chandragupta met, which if true would mean his rule started earlier than 321 BCE. As Alexander never crossed the Beas river, so his territory probably lied in Punjab region. He has also been variously identified with Shashigupta (who has same etymology as of Chandragupta) of Paropamisadae (western Punjab) on the account of same life events. With the help of the small Janapadas of Punjab, he had gone on to conquer much of the North West Indian subcontinent. He then defeated the Nanda rulers in Pataliputra to capture the throne. Chandragupta Maurya fought Alexander's successor in the east, Seleucus when the latter invaded. In a peace treaty, Seleucus ceded all territories west of the Indus and offered a marriage, including a portion of Bactria, while Chandragupta granted Seleucus 500 elephants. The chief of the Mauryan military was also always a Yaudheyan warrior according to the Bijaygadh Pillar inscription, which states that the Yaudheyas elected their own chief who also served as the general for the Mauryans. The Mauryan military was also made up vastly of men from the Punjab Janapadas. Chandragupta's rule was very well organised. The Mauryans had an autocratic and centralised administration system, aided by a council of ministers, and also a well-established espionage system. Much of Chandragupta's success is attributed to