Complex sentence: This Royal Decree was officially issued in the name of Guangxu Emperor, bearing his official Royal Seal, who was in effect under house arrest, ordered by Empress Dowager Cixi at that time, as the full administrative power was in the hand of the Empress Dowager.
Split into simpler sentences: This Royal Decree was officially issued in the name of Guangxu Emperor, bearing his official Royal Seal. The Emperor was in effect under house arrest, ordered by Empress Dowager Cixi at that time, and the full administrative power was in the hand of the Empress Dowager.