[2] After receiving his early education at a Mission School in Canton,[3] Yung studied at Yale College to become, in 1854, the first-known Chinese student to graduate from an American university.

[4] In 1851, at the end of his freshman year, Yung wrote to Albert Booth, a fellow alumnus of Munson Academy and "old Yale, where you have the satisfaction + honor to have gone through."

After finishing his studies, Yung returned to the Qing dynasty and worked with western missionaries as an interpreter.

In 1863, Yung was dispatched to the United States by Zeng Guofan to buy machinery necessary for opening an arsenal in China capable of producing heavy weapons comparable with those of the western powers.

He persuaded the Qing dynasty government to send young Chinese to the United States to study science and engineering.

[6] In 1874, he and the Hartford Pastor Joseph Twichell traveled to Peru to investigate the living conditions of Chinese coolies working there.

In 1908, Yung joined "General" Homer Lea, the former American military advisor to Kang Youwei, in a bold and audacious military venture in China called the "Red Dragon Plan" that called for organizing a revolutionary conspiracy to conquer Liangguang.

Through Yung, Lea planned to solicit a united front of various southern Chinese factions and secret societies to organize an army that he would command for the revolution.