 All six monarchies in the European Union are constitutional monarchies.In all six monarchies that are in the EU, the monarch is legally prohibited from using political power, or the monarch does not utilise the political powers vested in the office by convention.At the dawn of the 20th century, France was the only republic among the future members states of the European Union; the ascent of republicanism to the political mainstream only started at the beginning of the 20th century.