In Volker Caumanns’ book,
Shakya-mchog-ldan, Mahāpaṇḍita des Klosters gSer-mdog-can (Wiesbaden, 2015), he presents material on an Indian monk in Tibet named Lokottara, who self-identifies as of the Sāṃmitīya nikāya, and says his home is in eastern India, in a place called Saṃgharatna.
This is 15th century. I know of a Saṃgharatna in Kerala, but not one in eastern India. Would anyone have a clue where that might have been (still is?), and what might correspond to it in today’s India?
Thank you.
Dan