The edicts matter to historians for a reason unconnected with their contents. In the thirteenth major rock edict Ashoka lists five kings to whom he says he has sent envoys, and the names are Hellenistic: Antiochus, and beyond him Ptolemy, Antigonus, Magas and Alexander. Those reigns are datable from Greek and Egyptian evidence, and their overlap fixes the passage to a narrow window in the middle of the third century BCE. It is one of the few firm chronological pegs in early Indian history, and the dating of the Mauryan dynasty, and through it a great deal else, hangs from it.
The inscriptions were also lost. The Brahmi script fell out of use and the pillars stood unread for centuries; a fourteenth century sultan of Delhi moved two of them without knowing what they said. James Prinsep deciphered Brahmi in 1837 and the emperor named in the texts as Piyadasi, the beloved of the gods, was then matched with the Ashoka of the Buddhist chronicles.
How Buddhist the edicts are is still argued. Ashoka names the Buddha, the sangha and specific texts in the minor edicts, and one inscription threatens expulsion for monks who divide the order. But the dhamma proclaimed to the empire at large is a civic ethic rather than a doctrine, addressed to a population of many persuasions, and Romila Thapar and others read it as a policy of imperial cohesion as much as a confession of faith.