What does Shizuru rule?

[Impossibly Diverse]

Shizuru is described as "Empress of Heaven", but her empire clearly neither encompasses nor is limited to Heaven. She is said to rule over the "divinities of Tian Xia", but what does that mean? She seems to have a well-defined sphere of authority, but elsewhere the deities of Tian Xia come across as being a fuzzily-defined set of gods united solely by being widely worshiped in one particular continent on the material plane, which seems like an odd way for gods to assign authority. So, what exactly does Shizuru rule?

[Beavois]

Well...Shizuru role as "Empress of Heaven" is kinda fuzzily defined. She seems to be a ceremonial/theoretical ruler of the Tian pantheon of deities, and her domain on the plane of Heaven is described as a sort of neutral-ground meeting place for the Tian pantheon. But it doesn't appear that she has true control over the other Tian gods. And she certainly wouldn't be the ruler of the entire plane of Heaven; the "Empress of Heaven" bit seems more metaphorical than anything.

She also has a specific link to the nation of Minkai; the imperial family there claims her as a divine ancestor. But she clearly leaves the ruling of the mortal realm to mortals. But she is influential in the rest of Tian Xia, too.

So...Shizuru seems to be perhaps the most influential god in the Tian pantheon on Golarion. But in cosmic terms, she's just one god of many. I guess--don't think there's a crystal-clear answer to this.

(And Shizuru is very clearly derived from the real-world Japanese Shinto imperial sun goddess Amaterasu.)

[The Raven Black]

Zeus being the king of the Greek deities did not really prevent them from doing mostly what they wanted, up to acting against his wishes.

In the end, I think such titles mean that the deity is the one kings and emperors pray to. And there is only one in a given Pantheon.