Classic Age around year 1

Parent universe: Reality

Kardashev

Value: 0.46
Min: 0.4
Max: 0.5
Confidence: CalculatedGuess

Pottery (ovens), but no other energy consuming industry. Manual labor (not changing per capita consumption), some animal labor, few wind and water mills. Still 200 W for most people. Total might be 250 W.

Population

Value: 100e6
Min: 70e6
Max: 200e6
Confidence: Canon

References:

Prehistoric Demography (Wikipedia)

Quick Wikipedia research. Error bars guestimated.

Many towns and cities in populated parts of the world but still hunter gatherers. Basically Han China and the Romans plus many regional Bronze Age powers.