Assyrian Empire: 247 years
Persian Empire: 208 years
Greek Empire: 231 years
Roman Republic: 233 years
Roman Empire: 207 years
Arab Empire: 246 years
Mameluke Empire: 267 years
Ottoman Empire: 250 years
Spanish Empire: 250 years
Romanov Russia: 234 years
British Empire: 250 years
Guesswho: 249 years