Joseph Conrad, "Karain, a Memory":
His smallest acts were prepared and unexpected, his speeches grave, his sentences ominous like hints and complicated like arabesques. He was treated with a solemn respect accorded in the irreverent West only to the monarchs of the stage, and he accepted the profound homage with a sustained dignity seen nowhere else but behind the footlights and in the condensed falseness of some grossly tragic situation.
This is about a ruler in the East called Karain. He is given a lot of respect by his subordinates. Conrad compares such respect with some "monarchs of the stage."
I can't find an explanation of this phrase. Does he mean those ones best on the stage like singers, poets, movie stars (I get it that they've appeared later, it's just an example) or is there a saying like this meaning something else?