The Greymane Wall was constructed after the end of the Second War, by Genn Greymane. It allowed the nation of Gilneas to isolate itself from the Alliance, due to a disagreement about the orcish internment camps.
The Greymane Wall portcullis is as close as any will get to seeing Gilneas. There are no guards, no vendors, no passers by. The gate never opens. It seems dead and deserted. 
However many refugees from the North attempt to find sanctuary with the Gilneans, camping by the portcullis in the hope they will be saved. They never see a citizen, and are easy pickings for the completely feral worgen that inhabit Shadowfang Keep and it’s surroundings.
Those in Gilneas are successfully escaping the plague, however the worgen 
curse has overtaken their population. This devastation means the Gilneans cannot help those refugees seeking an escape from the plague.
It is rumoured that the Gilneans have discovered a partial cure for their condition, however, and that this allows them to transform at will, and keep their minds once transformed.
The incoming Cataclysm will shatter the Greymane Wall, and the worgen will join up with their old allies, the Lordaeron humans, as well as the rest of the Alliance, to fight against whatever Cataclysm may bring…
Worgen-puppy-people! I’m really looking forward to playing through the Worgen story lines in Cata