By the sixth century BC, the Vedic tribes (the Janapadas,
from 'Jana', 'people' or 'tribe', and 'pada', or 'foot') had
subdivided into sixteen great Mahajanapadas ('maha' means 'great').
These were Magadha (southern Bihar), Kashi (Varanasi in
Uttar Pradesh), Kosala (Awadh in Uttar Pradesh), Anga (Eastern
India), Vriji (northern Bihar), Malla (north-central India),
Panchala (Budaun, Farukabad, Uttar Pradesh), Matsya (Jaipur, Alwar,
and Bharatpur in Rajasthan), Surasena (Mathura in Utar Pradesh),
Ashmaka (south of the Vindhya Mountains, in Maharashtra), Avanti (Madhya Pradesh),
Gandhara (Kandahar in Afghanistan),
and Kamboja (the Hindu Kush region in Afghanistan).
Eventually four major kingdoms became the most powerful.
These were Kosala, Kashi, Magadha and the Vriji confederacy.
In the first half of the
first millennium BC, Magadha was ruled by
King Bimbisara of the Haryanaka dynasty. He was murdered by his own
son, Ajatshatru, who then ascended the throne.
Kosala, Kashi and Vriji and became the undisputed king of northern
India. As destiny would have it, Ajatashatru was also killed by his
own son for the Magadha throne. This history of parricide was
repeated amongst successive kings (Udayabhadra, Anirudha, Munda, and Nagadasaka) until
the dynasty was overthrown amidst a popular rebellion, after which
their minister, Shishunaga, became king. However, Shishunaga was murdered (as per R Thapar)
by a usurper (although some
say that the murder victim was his son, Kalasoka, including L Prasad.
According to other sources there were at least five kings ruling
after him - the sons of Kalasoka: Nandivardhan, Kshemadharman,
Kshemajit, Bimbisara II, and Mahanandin).
usurper's name was Mahapadma Nanda, a shudra by birth who founded the Nanda dynasty.
Under the Nandas, Magadha emerged as a very powerful empire. Most of
the surrounding kingdoms either merged into Magadha or ended up as
its vassals. This position with Magadha being totally dominant remained
the case for centuries to
come. There were said to be eight kings (Pandhuka, Panghupati,
Bhutapala, Rashtrapala, Govishankara, Dashasidhkhaka, Kaivarta,
and Dhanananda) who followed after Mahapadma Nanda.
Later the region of Afghanistan came under the Achaemenid rule of
Cyrus, the king of Persia.
In 326 BC, after defeating the Achaemenid
King Darius, the joint
armies of Macedonia and Greece marched under Alexander the Great into the
Indian subcontinent, acquiring one small kingdom after another.
Alexander's most famous battle, at Hydapses against King Puru (Porus) of
region, is vividly documented.