Question

which kingdoms were involved in the struggle for kannauj
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Answer 1

Here

Since 8th country the Palas, The Gurjras – Pratiharas and Rashtrakutas were engaged to control Kannauj

One major cause was a city of Kannauj in North India. Kannauj was rich in wealth and resources. ( minerals. agriculture and trade)

There was a fight to control the wealth as well as the fertile of Gangetic Valley.

Continuous fights weakened all the three and within 100 years the power of three declined.