More Canadian oddities:
Canada always starts Catholic, while every new city get Protestantism, almost the very next turn. This entire dynamics seems to be hardcodded and never takes into account the situation on the ground. This applies to the cases when Montreal is not even settled by Catholic France. Meaning I start Catholic on empty tile, found Montreal, get Protestantism the very next turn, while being Catholic all this time without a single Catholic city after Turn 3.
On turn 3 it is possible to unintentionally capture an Indy city, if you are at war with them from turn 1. Basically I failed UHV because and Turn 3 I got a message you have captured that Lourdes-(ridiculously long city name here) city.
Also Americans seem to care about Canadian lands more than California, for example.
P.S. As a side note, new culture and stability rules produce very strange and different Earths in 1860. Big players are often gone: No Turkey (Moors owning Istanbul), no England, no France. Japan is always owning 2 tiles on Korean peninsula. Very weird cultural borders in Europe (enclaves).