/s The United Kingdom of England and Scotland, the Principality of Wales, the subject territory of Ireland (Let alone Normandy and Gascony) were famously lacking in linguistic, religious, and cultural differences back when they were a great power. /s
I feel like the answer to the first is "name one". He can't mean any Chinese dynasty, the Mongols, any of the Islamic caliphates, the UK, France. Maybe he means Bronze Age Egypt? They kept hiring all the Nubians they could get though.