This is a double premiere - for the first items converted from Crusader Kings III for Sims 4 and also for Deco Objects for your world - Hood Deco Objects. About Crusader Kings III (CK3) - it is a strategy game from Paradox, set in medieval times (more precise 1066-1452) and it scopes a wide range of the cultures of the time. In the game you conquer land and build blood lines. The game is played on a map but there is no building or live simming - so in this way, Sims 4 can fill that void.
You can place Hood Deco Objects with the help of T.O.O.L by @twistedmexi - be sure to read the instructions for the mod if you are not already familiar. Same creator is also working on the much-anticipated CAW - Create-A-World-mod - currently still in alpha development.
Note: these are NEW world deco objects, but that category was missing, so I had to label them as default replacements.
Now, about these ships.
There are two ships - the Knarr and the Longship. The Knarr (also means "creak" in Swedish :) ) is the smaller one, a Norse merchant ship. The bigger Longship is a war ship.
The Knarr is a converted mesh/texture from Paradox. The Longship comes from the CK3 mod Community Flavor Pack, by El Tyranos. There are two versions of the ships - a sailing one and a portside one, with sails tucked away and the shields used elsewhere. NOTE: they are debug world objects, so activate debug items in build mode. Search for CK3 to find them.
The Knarr and the Longship resting at Windenburg Island