In 1820, shortly after the death of Jiaqing Emperor in the Chengde Mountain Resort, Mianyu was granted a title of Prince Hui of the Second Rank (惠郡王)[1] by Empress Dowager Gongci as the successor to the imperial throne has not been appointed.
[3] In 1851, Mianyu was appointed as a commander of Manchu forces of the Bordered Yellow Banner and was entrusted with managing the affairs of the Gioro family school.
[5] In 1856, when Second Opium War broke out, Mianyu was in charge of administration of Beijing[6] and was vested with powers of Generalissimus Possessing a Mandate, which meant that he would be one of the commanders of Eight Banner Forces.
[7] When Sengge Rinchen suffered several defeats in Tongzhou, Mianyu sent emergency so as to protect Five Capitals (places where Qing dynasty emperors used to reside during the imperial tours).
In 1837, he married another Lady Guwalgiya, daughter of Guiliang (桂良)[12] and elder sister of Princess Consort Gongzhong of the First Rank (Yixin's wife).