From Emperor Hui on, the posthumous titles of the Han emperors began with
孝 'filial', to show a dynasty that ruled through filial piety. Emperor Wu is formally
孝武皇帝, but histories drop the
孝 and write
汉武帝. Later dynasties gave
孝武 as a title of its own, to
司马曜 of the Eastern Jin,
刘骏 of the Liu Song and
元修 of the Northern Wei.