I have started a custom game with many players. I am playing as Dutch, and one of the AI players is also Dutch; his lands are also "Dutch Colonies" etc.

I have stumbled upon a village where that AI has set up a mission. And the next turn I have got a Converted Native from that mission. Nice. :)

5 way multiplayer, 2 of us are spain (different leaders).
I am receiving the other spains converted natives, even though I had not met him!
(easy way of opening up the map!)

Yes noted for the unofficial patch.

The bloke who was the other spain side admitted he was getting my converts and keeping them! After I gifted the ones I got off him back as well! Git.