Introduction

Geography

Asheareth is considered to be an incomplete sphere, with Gates along the edges, and Chaos behind and above. If we agree that the Second Gate is in the upper part of a round flat map, then the Gates are positioned this way, clockwise: Second, Fourth, First, Fifth, Third. The Sun and the Moon are the Sun and the Moon Beasts respectively, whose route through the sky is fixed - it is the diameter of our map-circle with from the First Gate.
Some cultures have north-south-west-east orientation system (four directions, based on the Sun Beast's movement), relying on the Sun's distance from the horizon to find the latitude.

Since Asheareth doesn't have any magnetic poles, there is no such thing as compass. In Astarion, however, Laya'shiya are common. These rely on Saya's influence spreading from the Second Gate. On one end of an arrow a Khai'li stone is positioned, whose manufacturing process is kept secret. These stones are repelled by Saya's presence, and the opposite end of the arrow will point to the Second Gate. If held level with the ground, the arrow will point slightly downward, the farther the user from the Gate. Laya'shiya usually have level (instrument) and marks, where the arrow will point from Asteya and how low will its end be.
Because of this, Astarion maps have the Second Gate at the top and concentric elipses surrounding it.
As stated earlier, Asheareth is not moving, and the Beasts' paths are fixed. Therefore, there are no "seasons". The climate depends on how far the region is from the "equator" (the line directly beneath the Sun Beast's path), and how far it is from the Second and the Fifth Gates. Around these the climate is much colder or warmer, respectively. Leysa and Kharta are cyclic changes in the size and strength of the Gates' influence areas. During Leysa the cold winds from the Second Gate become more intense, and warmth of the Fifth Gate subsides, and vice versa.

Cultural perspective

It is impossible to write without a perspective. Here, Asheareth is described from the perspective of Astarion and, perhaps, some members of the Court. Most of these nations are far from close, post-industrial societies, and few have complete knowledge of their region, let alone foreign lands. Some of the information given are common rumors, superstitions or assumptions, that should not be treated as tested and true scientific facts.
In Astarion, literacy is limited to the closed community of the nobles and the Whisperers, the scribes. In the Court, to the nobles and the priests. The Touched are the only ones to actively research and classify, but they keep their findings to themselves.
Here, the information is something a curious and wealthy merchant or a noble might know. In time, here might appear something that only a Whisperer or a fearless traveler know.
Astarion and the Court despise Kashta, and no one really cared to research their customs and traditions. There can be vast and unknown lands beyond theirs, beyond the oceans and the Shattered Lands, or there can be nothing.
The followers of Raitha zealously believe in their gods and their power, while Astarion considers them pagan fantasies, and vice versa. It is your choice, whose perspective to choose.

Politics

Astarion is a strong colonial country with a single deity, Askaena, considered to have come from elsewhere. Astarum are conservative and proud, and have tensions with Kherala, the Court - theocratic federation of five members across the mountains. These five members have their own tensions and alliances as well, and some can be subdivided into yet more separate peoples and states.
Lashtreenh monks inhabit the eponymous mountains, and worship the Earth and the Wind. They do not have a central government, but can be divided based on who they worship more - the Earth or the Wind.
Beyond these mountains live numerous barbarian tribes and small countries. These used to be on the coast of the Ocean of Despair, the Sunset Ocean and beyond the mountains on the opposite side of Astarion, but were long conquered by the Court and Astarion.
All of these are human countries, but there are two other races-species that need to be taken into consideration. First of them are the Scaled, humans with many reptile or snake-like traits, who inhabit Astarion and worship Askaena, but are considered subordinate to the human Astarum.
The second are Kashta - savages, that live in the steppe beyond the Wall, in the Cestorian jungles, Lashtreenh moutains and in the Buried Cities. No one knows the extent of their territories, and they usually mark the edge of known lands.
The Undying can be considered a separate race, since they have a number of key differences and are quite separated from the societies of the Unworthy.

Magic

Superstition and folklore are common among the peoples of Asheareth. As said earlier, none of this has been tested, and while some believe, some don't. Choose the perspective you like most.