February 12, 1912: Regent Empress Dowager Longyu abdicates on behalf of her ward, Emperor Puyi, bringing end to the Qing DynastyFebruary 14, 1912: Arizona admitted as 48th state of the U.S.February 12, 1912: Emperor Puyi (standing) abdicates from the throne, bringing end to Qing dynastyFebruary 13, 1912: Sun Yat-sen resigns as President of the rest of China as monarchy ends