But still there is nothing wrong with the word "India" in this context. Brahmagupta was a worshipper of Shiva who lived in Rajasthan. He fits in perfectly well

But still there is nothing wrong with the word "India" in this context. Brahmagupta was a worshipper of Shiva who lived in Rajasthan. He fits in perfectly well with Indianness both modern and ancient. Now it is interesting that the words "India" and "Hindu" are western (mostly Iranian) impositions. Perhaps Brahmagupta would have found the word "Bharat" less alien. But since the topic of the article is about how a particular Indian idea was spread and developed further west, the name is perfectly appropriate. P.S. I also like John Keay's book.