What is a Constitutional Monarchy?

As Karl Loewenstein categorized, parliamentary constitutional monarchy has not been demolished in history, unlike absolute monarchy. Certainly, there have been strong anti-monarchical opinions since the age of Thomas Paine, but as Walter Bagehot stated, the British constitutional monarchy has been based upon the people’s strong support since the Victorian Age. It is the main reason why the Japanese adopted such a democratic constitutional monarchy in imitation of the British style after World War II. Moreover, they selected the word “symbol” as a position for the new-born emperor in their Constitution in 1947 from a famous book of Bagehot, The English Constitution.