Origin of Brunei Darussalam

I did not realise that there would be a big debate on what an 'empire' is when I stated that Brunei lost its huge empire. Of course in comparison to the Roman Empire or any of the other 'Empire', the Brunei Empire was relatively small. But at its height, it is said to have covered the whole of Borneo Island and all the islands in the Southern Philippines and some have said the empire also