Templehelm is believed by many to be where the Deities of Ateon draw their power. It is only known to be Templehelm that such direct communion and influence from the Deities is felt. According to the Emeraldites, numerous Deities have only come to be in Templehelm well after the Emeradlites arrived. Prior to this, The Emeradlites knew only of Planu, Pallus and Zelphair to exist.
The origin stories and purpose of these Deities varies between Creeds and even individuals - but the Emeraldites prescribe to the understanding that these are the "Empowered Souls" created by Planu - the Deity of the Plains and Mountains. However some have suggested that these "Sired Divines" are only different personalities or characteristics of Planu.
Aligning with a particular Deity brings certain rewards - and as the Deities are believed to be omnipresent and intrigued by the actions of their followers - many prayers are answered and a Deity is the greatest ally one could have when going into battle.
For the most part - Deities have proven to only wield power in their own realm - and it is in a Deities realm that interaction with one is likely to occur. For example - building a shrine to Wildaven in the Desert is pointless, as Wildaven most likely will not be in it's presence. Similarly prayers to Netharna when you are not in the Nether, will most likely not be answered.
Note: There are many tales and rhetoric about there actually being more than seven Deities - However these other Deities are seen as being much older and very little is known about them as they rarely make their presence felt - And these Deities are not known to accept followers.