Proto-Finnic arrived to Southwest Finland from Estonia, through the sea. This is something virtually all linguists agree on.
Later on other groups of Proto-Finnic moved east from Estonia and became Karelians. Those people populated Finland, and merged with the West Finns, forming the Savonian and Karelian dialect groups.
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u/Kata_Komb larping as Nordick 1d ago
Estonian language didn't come from Finland. If anything, it's the other way around.