|A.K.A.||Brithadratha, Brhadrata, Bṛhadratha, Brihadrata|
Brihadratha Maurya (IAST: Bṛhadratha Maurya) was the last ruler of the Maurya Empire. He ruled from c. 187 – c. 180 BCE. He was killed by his general, Pushyamitra Shunga, who went on to establish the Shunga Empire.
According to the Puranas, Brihadratha succeeded Shatadhanvan and ruled for seven years. Mauryan territories, centred on the capital of Pataliputra, had shrunk considerably from the time of Ashoka when Brihadratha came to the throne.
Invasion of Demetrius I
In 180 BCE, northwestern India (parts of modern day Afghanistan and Pakistan) were attacked by the Greco-Bactrian king Demetrius. He established his rule in the Kabul Valley and parts of the Punjab region. The Yuga Purana says that the Yavana army led by King Dharmamita (Demetrius) invaded the Mauryan territories during Brihadratha's reign and after occupying Panchala region and the cities of Saket and Mathura, they finally captured Pataliputra. But soon they had to leave for Bactria to fight a fierce battle (probably between Eucratides I and Demetrius).
Usurpation of power by Pushyamitra Shunga
He was killed in 180 BCE and power usurped by his general, Pushyamitra Shunga, who then took over the throne and established the Shunga Empire. Bāṇabhaṭṭa's Harshacharita says that Pushyamitra, while parading the entire Mauryan army before Brihadratha on the pretext of showing him the strength of the army, crushed his master.