What made viking ships and scandinavian architecture unique?

In comparison to others, the Vikings were quite advanced in some areas. Their shipbuilding and combat abilities were unrivaled. They did, however, need to plunder and conquer to keep up with their rising numbers. Their ships and swords were quite detailed, runes were engraved into their weapons, and creatures were carved into their ships. The Vikings discovered how to construct structures out of two types of wood: birch and coniferous trees. To adapt to the material they chose, they created two separate construction styles.

i think these large heads represent their gods and i do think they were worshiped by the people. if there was only one head and no heads around it i think it would be monotheistic but if there are several heads close to each other it could be polytheistic.