User blog comment:Zippertrain85/Dunmer/Argonian slavery, my thoughts./@comment-1600847-20140116181200

A few things:

1) Tiber Septim DID invade Black Marsh, but only the outer swamps and the eastern/southern coastlines. It was only the central swamps he didn't invade since they had no strategic value.

2) Lore states that the Dunmer slavers only attacked the outer swamps of northern Black Marsh for slaves, never the inner swamps. The outer swamps are shown to be habitable for non-Argonians in The Infernal City.

3) The reason the Dunmer never got a retaliatory invasion from the Argonians is probably because of the Tribunal's power. Even Tiber Septim didn't want to mess with them. The Argonians only realised their potential for kicking divine ass AFTER the Oblivion Crisis - which is also after the Tribunal lost their power/vanished/got killed.

And even without the Tribunal, the Dunmer are quite powerful. The Dunmer army in the fourth era was able to stop the Argonians, even after losing so many of their forces in the Red Year. They're a force to be reckoned with, Tribunal or no.