When in history...

[blitzkrieg80]

what about the Minoans and the Myceneans for that matter?

The Huns and Khazars formed something of an empire in the usual advanced notion of khan and khaganate along the steppe.

the Gothic title Reiks (borrowed from Celtic rix) very much implies an advanced concept of kingship and overlordship of multiple peoples and sub-rulers on par with empire, such as that under Ermanarik.

Come to think of it now... what exactly is the criterion for "empire" for this thread? It surely isn't the title Imperator or "General" and it also isn't the idea of Principate and status as "First Citizen." Many of those listed, such as the Normans probably shouldn't qualify. A successful kingship which stretchs far and encompasses different peoples is still a kingship... there is an important distinction between regules and rex... thus, concept of government and authority of the "emperor" over his sub-kings becomes an important determination. The language of the titles used by those empires become more important than our English translation... Austria (Osterreich) and France (Frankreich) are still called "Empires" in the Modern German names for those countries, while Russia is not, and if anything these days, Russia is still more of an empire than either of those. the Persian shāhanshāh "king of kings" might be the first true emperor in that the title actually meant more than the title of those before... it is not enough to simply have territory and power, language and perception must also recognize the uniqueness of that position in contrast of those under it