Originally Posted by
Steampunkette
It's possible Adverse Possession laws might not exist on Azeroth, but the legal term originated in Medieval England... so... y'know. The principle exists.
In common law it was 12 years, in England, before the Land Registration Act in 2002, which codified it specifically into a method for a Common Law Adverse Possessor to actively register as the current owner of the land, rather than having it remain Unregulated entirely.
Though, again, I'll note that it's -arguable- that Adverse Possession comes in to strip away Calia of her ownership rights.
All of that said, I think the Forsaken would -welcome- her return as a member of their Royal Family. SYLVANAS wouldn't welcome her, and might try to kill her or raise her. But the Forsaken? They'd probably be pretty happy to have her come back, hopefully marry, and raise a new royal family.
They just probably wouldn't depose Sylvanas to install Calia as their monarch, of course. They'd just have her around as a powerless figurehead that represents ties to a noble heritage.
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Stormwind was not the capital of the Alliance of Lordaeron. Lordaeron was.
And yeah. There -are- some Lorderonian citizens in Stormwind who either have claim to lands in Lordaeron, or do not if they renounced such rights and became citizens of Stormwind (Though that depends on the laws of Stormwind itself). If they're still refugees, though, they'd have the right to try and reclaim their land. Stormwind, though, does not, even if some small portion of it's populace is Lordaeronian by birth or marriage.