According to an ancient Sri Lankan source, the Mahavamsa, Greek monks seem to have been active proselytizers of Buddhism during the time of Menander: the Yona (Greek) Mahadhammarakkhita (Sanskrit: Mahadharmaraksita) is said to have come from "Alasandra" (thought to be Alexandria of the Caucasus, the city founded by Alexander the Great, near today’s Kabul) with 30,000 monks for the foundation ceremony of the Maha Thupa ("Great stupa") at Anuradhapura in Sri Lanka, during the 2nd century BC:

"From Alasanda the city of the Yonas came the thera ("elder") Yona Mahadhammarakkhita with thirty thousand bhikkhus." (Mahavamsa, XXIX)

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