Greenaere is a small crescent-shaped island (perhaps resembling a banana) off of the west coast of the main continent that includes the Dragaeran Empire.
The people of Greenaere appear to be physically of the same racial stock as Dragaerans, being very tall and thin, and presumably as long-lived. However, unlike Dragaerans, they do not maintain House segregation.
This may make them the equivalent of Jhereg (or perhaps Teckla?) in the eyes of Dragaerans of the Empire, in that Greenaerans are apparently all crossbreeds. Presumably, Greenaerans don't care what those of the Empire think of them.
The social structure appears to be a completely independent monarchy and nobility. The palace is not particularly ornate, and the king is not very well guarded; this may hint that political power is more decentralized than otherwise.
While there does not appear to be a standing army or navy, the Greenaerans have a sufficiently large fishing fleet with skilled sailors that can act as a navy in times of war.
There are vast quantities of Gold and Black Phoenix Stone, abundant on and under the island, which will interfere with the use of most magics. Indeed, those who have links to the Orb will be aware that the link is temporarily severed some distance off the shore of the island itself (the link will be restored after passing beyond the influence of the Phoenix Stone).
As a result of the effect of the Phoenix Stone, neither sorcery nor witchcraft are generally possible on Greenaere. However, the psychic bond between witch and familiar is not affected. In addition, Elder Sorcery can be used to create amorphia there, by those with the bloodline to do so. Someone with strong psychic powers can sometimes force through a communications link, although the effort is tremendously exhausting.
Vlad Taltos travelled to Greenaere in Phoenix, and assassinated the King of that island, and escaped with the help of Aliera and Morrolan. This launched a war between Greenaere (later joined by Elde Island as an ally) and the Dragaeran Empire.
However, after the Greenaere-Elde Island alliance sank one of the ships of the Dragaeran navy, Vlad, with the assistance of Sethra Lavode and Daymar, was able to bypass the sorcery-defeating effect of the Phoenix Stone, appear before the new King of Greenaere with Aliera and Morrolan, and negotiate a peace treaty, ending the war.