[To dismiss it so lightly? An empire bigger than his own? Now Iskandar must know what deep, dark secret Richar is hiding that is causing such a reaction.
Iskandar's own son, any of his descendants or immediate family, didn't survive long enough to be able to achieve greatness. So it shouldn't be surprising that such a flippant attitude to one's successors' achievements is difficult for him to understand.]

I see nothing wrong in feeling pride in accomplishments of your people. Whether it was by your hand or by your example they are still your people.
It must have been a magnificent empire then. Did they reach India perhaps?