Log on to Steam from an Australian account and you'll be greeted by a banner for Crusader Kings 3 saying, "NOW AVAILABLE!" But click through to its store page and you'll be told, "In agreement with the publisher, Crusader Kings III is currently not available for purchase in your region." I tried to buy it from the Paradox Store in Australia, and at the checkout was greeted with the message, "Crusader Kings III is currently not available for purchase in your country. We're working on resolving this as soon as possible."
Last month the Crusader Kings Twitter account said that, "Currently the sales of CK3 in Australia & New Zealand are halted as we are investigating matters having to do with age ratings. We’re working on resolving this as soon as possible and Paradox will honor already placed pre-orders." The issue was cleared up with regards to New Zealand before launch, but apparently the same isn't true of Australia.
Normally in these cases it's Australia's Classification Board that's to blame, but Crusader Kings 3 doesn't even have a listing there. Meanwhile its predecessor, Crusader Kings 2, got away with a rating of PG for "mild violence" and "online interactivity". What could be so shockingly different about Crusader Kings 3?
In a statement to Kotaku Australia, Paradox said that, "Up to this point, we've been handling the ratings classification issue through an intermediary body, not the classification board directly. We don't have any more details to share, I'm afraid, since a lot of this process has to, necessarily, be kept between the parties involved. We hope that things will be resolved soon, so our Australian audience can enjoy Crusader Kings III."
In the meantime, Crusader Kings 3 can apparently be played through Xbox Game Pass in Australia just fine.