At what point in history did the British Monarchy go from having power to becoming a figurehead? The shift obviously came after 1215 and the Magna Carta, and also after the English Civil War. I’ve heard it can be traced to the house of Hanover, but when and why?

More can be written on this, but you might be interested in the FAQ section "How has the power of the British monarch changed over time?" . Some discussions deal with decreases in royal power, but the one that most discusses the figureheaditude is "In Great Britain, when did Parliament really become more powerful then the crown?" by /u/Three_Trees .

This is not to discourage discussion. Further questions, data, and debate are welcome.