Belgium is a relatively young country, but has been a constitutional monarchy since its founding in 1830. After originally being part of the House of Saxe-Coburg and Gotha, since 1920 it has been the House of Belgium. Find out all you need to know… Belgium is a relatively young country, but has been a constitutional monarchy since its founding in 1830. After originally being part of the House of Saxe-Coburg and Gotha, since 1920 it has been the House of Belgium. Find out all you need to know…