I consider the Scandinavian (Nordic) countries Socialist, as would most-anyone in Scandinavia as far as I've seen.
Current PM in Denmark is the head of the Social Democrats.
Previous PM in Sweden represented the Swedish Social Democratic Party.
In Denmark, Sweden, Norway and Finland, socialist parties are amongst the largest parties.
(Norway recently turned toward Neo-nazism, so not going to use them as example)
Being Socialist doesn't explicitly impair your ability to have a free market.