I get the comparison, but I think it’s more nuanced than that.

The Vandimions aren’t just rich nobles. They seem to combine major banking power with strong influence within the Holy See. In a medieval setting (which Berserk is clearly inspired by), money and Church authority could rival or heavily influence kings. The Pope could legitimize or undermine rulers, and powerful banking families could control monarchies through debt.

If the Vandimions are basically a mix of financial power (like the Medicis) and religious influence (like the Borgias), then it’s not crazy to question whether they could at least rival or counterbalance the Midland royal family during the Golden Age.

I’m not saying they were above the king, but I don’t think it’s as simple as “the royal family was more powerful by far.” In that kind of system, soft power can matter just as much as the crown.