Gurjara-pratihar
The Gurjara-Pratiharas were instrumental in containing Arab armies moving east of the Indus River. Nagabhata I defeated the Arab army under Junaid and Tamin during the Caliphate campaigns in India. Under Nagabhata II, the Gurjara-Pratiharas became the most powerful dynasty in northern India. He was succeeded by his son Ramabhadra, who ruled briefly before being succeeded by his son, Mihira Bhoja. Under Bhoja and his successor Mahendrapala I, the Pratihara Empire reached its peak of prosperity and power. By the time of Mahendrapala, the extent of its territory rivalled that of the Gupta Empire stretching from the border of Sindh in the west to Bengal in the east and from the Himalayas in the north to areas past the Narmada in the south. The expansion triggered a tripartite power struggle with the Rashtrakuta and Pala empires for control of the Indian Subcontinent. During this period, Imperial Pratihara took the title of Maharajadhiraja of Āryāvart.
The metropolis of Kannauj had suffered a power vacuum following the death of Harsha without an heir, which resulted in the disintegration of the Empire of Harsha. This space was eventually filled by Yashovarman around a century later but his position was dependent upon an alliance with Lalitaditya Muktapida. When Muktapida undermined Yashovarman, a tri-partite struggle for control of the city developed, involving the Pratiharas, whose territory was at that time to the west and north, the Palas of Bengal in the east and the Rashtrakutas, whose base lay at the south in the Deccan. Vatsraja successfully challenged and defeated the Pala ruler Dharmapala and Dantidurga, the Rashtrakuta king, for control of Kannauj.
Around 786, the Rashtrakuta ruler Dhruva (c. 780–793) crossed the Narmada River into Malwa, and from there tried to capture Kannauj. Vatsraja was defeated by the Dhruva Dharavarsha of the Rashtrakuta dynasty around 800. Vatsraja was succeeded by Nagabhata II (805–833), who was initially defeated by the Rashtrakuta ruler Govinda III (793–814), but later recovered Malwa from the Rashtrakutas, conquered Kannauj and the Indo-Gangetic Plain as far as Bihar from the Palas, and again checked the Muslims in the west. He rebuilt the great Shiva temple at Somnath in Gujarat, which had been demolished in an Arab raid from Sindh. Kannauj became the center of the Gurjara-Pratihara state, which covered much of northern India during the peak of their power, c. 836–910. Rambhadra (833-c. 836) briefly succeeded Nagabhata II. Mihira Bhoja (c. 836–886) expanded the Pratihara dominions west to the border of Sind, east to Bengal, and south to the Narmada. His son, Mahenderpal I (890–910), expanded further eastwards in Magadha, Bengal, and Assam.