There’s a possibility that some of you know that as part of my interest in the ancient world over the last few years, I’ve picked up a couple of books on the Indo-Greeks of Bactria which was an aftermath empire that resulted from Alexander The Great’s conquests. It’s not quite a successor state like the Seleucid Empire or Ptolomaic Egypt, but it’s close to that. I’ve recently learned that there’s a case to be made that Greeks were the first or among the first non-Indian Buddhist monks. There was pretty extensive cultural exchange between India and Persia even before Alexander and some evidence that the Greeks were familiar with and had written down some of the teachings of Buddhism even before Alexander.
Read a little about Greco Buddhism here on Wikipedia.