The Holi festival is an ancient Hindu festival with its cultural rituals. It is mentioned in the Puranas, Dasakumara Charita, and by the poet Kālidāsa during the 4th century reign of Chandragupta II.
This gives some idea as to when Holi started being celebrated. I'm wondering if we can be more precise.
Question: When did Holi start being celebrated?
I found descriptions at various other sites (very ancient in its origin theholidayspot.com; and ancient festival ancient-origins.net) However, these don't give the time period, just saying it's "ancient" (which is vague).
I didn't find an answer at within this related question: Why do people celebrate Holi? Why do they throw colored powder at each other?