And again, another speculation about the warriors of darkness = old warriors of light

[Kallera]

snip

Stating that we don't know the past is a odd idea. Considering there are some that played that past. It could be that we don't know Derplander, or what he was doing in Carteneau "With the main host" compared to what we were doing in Mor Dhona.(As in, it was a large battle, and multiple people were taken.) But to say we don't know the past anymore calls into question our identity, or even if we are "human".

I don't think the lore treats it as we are the only ones to come back, so much as we are the only ones to live up to the legend. I'm sure there's more detail (or a correction) on this though.