Rhododendrons!

[Luzzly]

Does anyone know if rhododendrons existed in Italy in Roman times?

[Mosaic]

This link suggests one type of rhododendron existed in southern Europe at the time concerned
https://cabiinvasives.wordpress.com/2013/01/30/rhododendron-ponticum-much-more-than-just-an-invasive-weed/
The 'ponticum' part of the name suggests Pontus, the ancient Greek name for the Black Sea coast
So I think the answer to your query is 'quite probably' but not all the showy varieties we have now.