How many enlisted US servicemen received battlefield
commissions/Combat Appointments during the Vietnam War? Can this be
broken down by branch of service, ie how many Army, how many Marines,
etc.?

Hi blot1-ga:

There is a lack of *precise* records of battlefield commissions during
the Vietnam War. However, what I've been able to find leads me to
believe that there were approximately 70 such honors given out in that
war.

The first place to look is the "National Order of Battlefield
Commissions", which was established in 1979. They can be found on the
web at:

http://www.battlefieldcommissions.org

Their history page at shows that while there were thousands of
battlefield commissions given in World War I and World War II, that
number decreased dramatically in Vietnam.

Let's look at the various branches of the service:

Marines:

"From 1963-1973 the Marine Corps Commandant appointed a permanent
Board with the mission of selecting those enlisted men of the Marine
Corps whose performance under fire while serving in Vietnam merited a
commission. A list of 62 enlisted men who were commissioned includes
one man who was killed before he could accept his commission."
From: http://www.battlefieldcommissions.org/history.htm

Army:

"The Department of Defense, in an official communication, has stated
that there were no battlefield commissions awarded by the Army during
the Vietnam conflict. In September, 1985, a letter was written to
General William Westmoreland who commanded all troops in Vietnam
requesting the General’s comments on the subject. General Westmoreland
replied: “We did commission several NCO’s on the battlefield in
Vietnam.”"
From: http://www.battlefieldcommissions.org/history.htm

Air Force:

"Two Air Force NCOs who were prisoners of war demonstrated such
outstanding leadership while in captivity that the senior officer at
their compound appointed them second lieutenants. After their release,
the Air Force publicly endorsed the appointments."
From: http://www.battlefieldcommissions.org/history.htm

Navy (this information isn't as reliable as for the other branches,
but it was the best I could find):

"In the Army you 
basically had to be a Service Academy graduate to make General in the
1950's.
More so for the Navy. Direct Commissioned officers weren't part of the
"system.
A "Battlefield Commissioned" officer was a kind of precarious
situation to be in.
I don't know if any other Service but the Army awarded such
commissions after WW II."
From: http://www.hollywoodnet.com/Lovett/chat/drawer16.html

Other sites also state that the rewarding of battlefield promotions
decreased after World War II:

"Finally, in 
wartime, Battlefield Commissions are sometimes given to fill command
slots, but this was
rarely done after Korea."
From: http://www.hollywoodnet.com/Lovett/chat/drawer16.html

I hope that this information is sufficient for your needs. If you have
any questions about what I've included here, please use the
clarification process before rating this answer.

Thanks. 

websearcher-ga

Search Strategy on Google:
"battlefield commissions" vietnam
"National Order of Battlefield Commissions"
"battlefield commissions" vietnam -"national order"
"battlefield commissions" vietnam navy -"national order"

So psyched to get this info so quickly, along with a list of
resources! Thank you websearcher!