GSK replied to Game world storyline problem December 2, 2021 @ 8:28:36 pm PST
Who's to say the Longship graves weren't dug out by the same people who made the swamp crypts? Or even still, who's to say the longship graves weren't created by other vikings wandering Valheim before you? Maybe a band of vikings met their fate, but a sole survivor placed the grave in remembrance of their comrades.
Some are the remains of those people before (and maybe after) the gods cast them down. A few of the other stones also mention some people coming to valheim with others. Some, especially with boat wrecks, could have just been others who crashed on the shore and were buried over time.
Plausible, but the stones around the longships seem to me like they would be moved there by someone or something which is where I am coming from.
6:13 am, December 3, 2021