At the height of Harsha's power, his realm covered much of northern and northwestern India, with the Narmada River as its southern boundary.

He eventually made Kanyakubja (present-day Kannauj, Uttar Pradesh state) his imperial capital, and reigned till 647 CE.

[8] Harsha was defeated by the Emperor Pulakeshin II of the Chalukya dynasty in the Battle of Narmada, when he tried to expand his empire into the southern peninsula of India.

[9] The peace and prosperity that prevailed made his court a centre of cosmopolitanism, attracting scholars, artists and religious visitors from far and wide.

[8] The Chinese traveller Xuanzang visited the imperial court of Harsha and wrote a very favourable account of him (as Shiladitya), praising his justice and generosity.

[8] His biography Harshacharita ("The Life of Harsha") written by the Sanskrit poet Banabhatta, describes his association with Sthanesvara, besides mentioning a defensive wall, a moat and the palace with a two-storied Dhavalagriha (white mansion).

[11][dead link‍][12][13][14][page needed] At the time of Hiuen Tsang's visit, Kanyakubja was the imperial capital of Harshavardhana, the most powerful sovereign in Northern India.

Jaiswal in Imperial History of India, says that according to a 7-8th century Buddhist text, Mañjuśrī-mūla-kalpa, Harsha was born of King Vishnu (Vardhana) and his family was of Vaishya varna.

On hearing about the murder of his brother, Harsha resolved at once to march against the treacherous King of Gauda, but this campaign remained inconclusive and beyond a point he turned back.

[8] The peace and prosperity that prevailed made his court a centre of cosmopolitanism, attracting scholars, artists and religious visitors from far and wide.

The Chinese traveller Xuanzang visited the imperial court of Harsha, and wrote a favourable account of him, praising his justice and generosity.

Pulakeshin then entered into a treaty with Harsha, with the Narmada River designated as the border between the Chalukya Empire and that of Harshavardhana.

However once in India, he discovered that Harsha had died and the new king Aluonashun (supposedly Arunāsva) attacked Wang and his 30 mounted subordinates.

Xuanzang states that Harsha banned animal slaughter for food, and built monasteries at the places visited by Gautama Buddha.

He erected several thousand 100-feet high stupas on the banks of the Ganges river, and built well-maintained hospices for travellers and poor people on highways across India.