Buddha worshiped as form of Vishnu in Amaravati

The Sātavāhanas ruled a large and powerful empire that withstood the onslaughts from Central Asia. Aside from their military power, their commercialism and naval activity is evidenced by establishment of Indian colonies in southeast Asia

It is believed that they were originally Brahmins, practicing Hindu religion (as per Sthala Purana of Amaravathi. Some rulers like Maharaja Satakarni are believed to have performed Vedic sacrifices as well.
They were not only worshipers of Vishnu and Shiva but also respected Buddha, but also other incarnations of, Gauri, Indra, the sun and moon.They were mostly Buddhistic Vaishnavites. Under their reign, 
Buddha had been worshiped as a form of Vishnu in Amaravati