Which past national commander held different national Legion offices simultaenously?

James A. Drain.

Drain, born in Illinois in 1870, had served in the Army during the Spanish-American War as well as World War I (and received the French Legion of Honor), and had risen from private to brigadier general in the Washington (state) National Guard. Formerly commander of the District of Columbia and a prominent attorney, he was elected national commander at the 1924 National Convention in St. Paul, Minn.

Drain’s term as commander ended in 1925, but at the November 1934 American Legion NEC meeting, he was elected to both the positions of national treasurer and national judge advocate. This unusual arrangement was part of then National Commander Frank Belgrano’s stated efforts upon his own election to "give the Legion a business administration" – to organize the organization, so to speak, to set it up for an effective future. Belgrano had also brought in Chicago accounting firm Ernst & Ernst to give an organizational report. It was more "economical" to pay a national judge advocate for a full-time position than to pay for retainers and fees whenever legal work was required.

Drain served in the two positions through the 1935 National Convention in St. Louis. He died in 1943.