Barbarians spawning on visible tile

[Zombie69]

I was playing a game and all of a sudden, at 575 BC, 4 barbarian swordsmen spawned on a visible tile and started moving towards my city. That tile and all other connected tiles had been visible for quite a while and was backed up against the ocean. I've never seen anything like this before. Here's a save game (press end turn to see it in action) and a screenshot of their position on the very next turn.

 

[civac]

These barbarians are due to an event. They are not normal spawns. Check event log.

 

[Zombie69]

I see no trace of them in the event log until they move into my city border one turn later.

 

[floydmcw]

4 swordsmen is an event.

Mongolia appears to have built the Great Wall. It's possible the event happened several turns ago, then when the Great Wall was built they were ejected from Mongolia onto the rice to your southwest.

(Also I don't see why barbarians couldn't spawn on that rice. It's not your territory and it's not within a 2-square distance of any of your units.)

 

[Zombie69]

Correct me if I'm wrong, but I don't believe barbarians can spawn on tiles that are visible by any of the civs. Whether that tile is visible from cultural borders or from units is irrelevant.

Interesting theory about the Great Wall but it was build in 2080 BC so that can't be it.

Anyway, I was unaware this event existed, thanks for letting me know! Weird that there's no mention of it anywhere in game but I guess some events are just hidden, or this was meant to apply to my neighbour.

 

[Zombie69]

Ah, found the event. 775 BC: A massive barbarian uprising is occurring. I guess it happened on the other side of the water and a city's cultural border expansion pushed them onto my side. Must be a weird corner case like you said with the Great Wall. Nice way to turn a defensive structure into some offence!