As far as sea creatures believe "Scaraqua" refers to both the entirety of the universe but depending on context "Scaraqua" can be defined as "all sea everywhere" particularly when contrasted with Scarterra which is effectively "all land everywhere." In context, if you the world "Scaraquans" pop up in this wiki, it essentially means "all sea based mortals everywhere" as opposed to "Scarterrans" that refer to "all land based mortals everywhere." Scaraquans and Scarterrans can and do interact with each other but Scaraqua and Scarterra are in many ways separate worlds. Scaraquans and Scarterrans speak different languages. Scaraquans and Scarterrans are governed by the same laws of physics and metaphysics are the same but they have different interpretations and myths explaining why reality works in that way.. Scaraquans and Scarterrans technically share the same world but they are mostly culturally removed from each other. They have the same gods, but the Scaraquans refer to the Nine by different names, different personalities, and sometimes by different genders.
Most Scaraquan mortals and beasts are concentrated in the warmer shallower waters fairly close to land masses. With deeper, colder and more remote waters boasting far less flora fauna and thus less people.
Scaraqua is vaguely similar to the real world's oceans but it's somewhat more densely packed. The chemical vents that support some deep sea life in the real world are both far more common and magically endowed with greater fertility.
History in Scaraquan is fuzzy because Scaraquan views on time are somewhat non-linear, and they don't bother codify dates as much as Scarterrans do.