Roman Warm Period 250 BC to AD 400

I maybe wrong, but I don't think I remember such a thing as the Roman Warm Period. I am much more familiar with the Medieval Warm Period 950-1250 AD.

This was not only the Roman, but also presumably also the Ancient Greece and Carthage Warm Period! So human civilization thrived when it was warmer. 

Of course, the real climate deniers try to downplay those two recent warm periods as mere local phenomena as opposed to global.

Roman Warm Period - Wikipedia