Chach (c. 631-671 CE) (Sindhi: چچ) was a Hindu Brahmin king of Sindh region of the Indian subcontinent in the mid-7th century CE. Chach expanded the kingdom of Sindh, and his successful efforts to subjugate surrounding monarchies and ethnic groups into an empire covering the entire Indus valley and beyond were recorded in the Chach Nama.
Chach was a Brahmin who rose to a position of influence under Rai Sahiras II, king of Sindh and a member of the Rai dynasty. Chach was the chamberlain to the King. According to the Chachnama, the last Rai emperor, Rai Sahasi II, died through illness without issue. By that time, Chach was in complete control of the affairs of the kingdom and had developed illicit sexual relations with Sahasi’s wife (queen Rani Suhanadi).[circular reference] When Rai Sahasi II was near death, Suhanadi explained to Chach that the kingdom would pass to other relatives of the dying king in the absence of any direct heir. Consequently, they hid the news of the king’s death until claimants to the throne were killed through conspiracy. Following this, Chach declared himself a ruler and later married Suhandi. This ended the Rai Dynasty and began the dynasty of a Brahmin dynasty called Chach dynasty. Maharana Maharat of Chittor, the brother of Rai Sahasi II invited Chach to a duel to seek revenge from Chach for killing his brother Rai Sahasi II and for usurping the throne of Sindh. [circular reference] He then launched a campaign against a succession of autonomous regions; he defeated his opponents along the south bank of the River Beas, at Iskandah, and at Sikkah. He sacked Sikkah, killing 5,000 men and taking the remainder of its inhabitants prisoners. A significant number of these captives were enslaved, and much booty was taken. After this victory, he appointed a thakur to govern from Multan, and used his army to settle boundary disputes with Kashmir. Chach also conquered Siwistan, but allowed its chief, Matta, to remain as his feudatory.
Later, he expanded his rule into Buddhist regions across the Indus River. These efforts culminated in a battle at Brahmanabad, in which the region’s governor, Agham Lohana, was killed. Chach remained in Brahmanabad for a year to cement his authority there, and appointed Agham’s son Sarhand as his governor; Sarhand was also wed to Chach’s niece. Chach took Agham’s widow as his wife, as well.
In 644, after the Muslim conquest of Sassanid Empire, the Rashidun army entered Makran and defeated Sindh’s army in the Battle of Rasil, annexing Makran (a traditional Persian territory under control of Rai dynasty at that time) and eastern Balochistan. Caliph Umar (634-644), however, for the time being, disapproved of any incursion beyond the Indus river and ordered his subordinates to consolidate their position west of Indus.