There's also the concept of Arkhand Bharat (https://en.wikipedia.org/wiki/Akhand_Bharat) which is the notion of a unified Indian subcontinent.
https://en.wikipedia.org/wiki/Religion_in_India
https://qz.com/india/1585631/the-ancient-connections-between...
In practice, a lot of Buddhists are very theistic. Many of them worship various gods and Buddhas.
In the West, Buddhism has been desacrilized to make it more palatable for Westerners, but in the East it's often way more religious and theistic, especially as the Buddhism that actually exists in those countries has often been blended with other indigenous religions which themselves are very theistic.