The third mammoth trial linked to the “Reich Citizens” extremist movement in Germany starts in the southern city of Munich on Tuesday. The trial concerns a group of suspects linked to Prince Heinrich XIII of Reuss, whom prosecutors say was a key figure in an alleged conspiracy to overthrow the German government. The Reich Citizens, or Reichsbürger in German, claim the historical German Reich of 1871 to 1945, with an emperor as head of state, is the country’s legitimate form of government. As such, they do not recognize the current German government or its institutions. The group was exposed fo…