Because it is one of the Big Three, Istara has a rich history that is heavily interwoven with other planets and species'. This is how it all fits together within the scope of the planet itself.
Vistians are the primary inhabitants of Istara. They yield magic and were one of the Big Three - the main races involved in the Great War.
The mythos of Istara is largely unknown. They are a particularly secretive species, which lends to their keeping secrets from anyone they haven't known for years. Despite this, they are especially religious and rigid in their beliefs.