Kāmpilya was the capital of southern Pāñcāla. It lay on the banks of the Gaṅgā. Southern Pāñcāla was the half of the Pāñcāla kingdom that Droṇācārya returned to King Drupada after the Droṇa–Drupada campaign.

When Arjuna captured Drupada and brought him before Droṇa, Droṇa divided Pāñcāla. He kept the northern half, with Ahicchatra as its capital. He returned the southern half, with Kāmpilya, to Drupada. So Kāmpilya remained Drupada’s seat. From here Drupada later began the Putrakāmeshṭi yajña (a fire rite performed to obtain a son), from which Dhṛshṭadyumna and Draupadī were born.

Drupada’s capital after the division

After Droṇācārya divided Pāñcāla, following the campaign in which Drupada was captured, Kāmpilya became Drupada’s smaller but still important capital. From this city Drupada planned his revenge. He searched for ṛshis (seers) powerful enough to perform a Putrakāmeshṭi yajña that could give him a son able to kill Droṇa.

The events that followed from this, the births of Dhṛshṭadyumna and Draupadī, made Kāmpilya a pivotal place in the Mahābhārata.

Brahma-datta’s Kāmpilya

Kāmpilya also appears in the Śānti Parva, in the Āpaddharma Parva, as the royal city of King Brahma-datta. His palace is the setting of the Brahma-datta–Pūjanī Saṃvāda (the dialogue of Brahma-datta and Pūjanī).

In this account the sparrow Pūjanī lived in the palace at Kāmpilya. She brought wonderful fruits for the king. Then a prince killed her chick, and she blinded the prince. The narrative uses this to teach about enmity.

Sources

Mahābhārata, Ādi Parva, Sambhava Parva, Chapter 138
Mahābhārata, Śānti Parva, Āpaddharma Parva, Chapter 139