Were all surgeons majors?

[Stryker65]

Been reading the OR, as I do, and I became aware of the fact that surgeons were sometimes referred to as majors. I of course understand the fact that surgeons were given the rank of major, but I always wondered whether they were actually majors. To be more clear, I'm wondering if, during battle, if the LTC and MAJ are wounded could the chief surgeon technically take command of the regiment? When I first heard about the surgeons-have-the-rank-of-major law, I was under the impression that they had that rank for two reasons: one, to pay them a fixed amount without having to create a new pay grade; and two, to rank them above other, subordinate surgeons. But overall, my main question is asking about whether a surgeon could be a Field Major.
Any thoughts?
-Stryker

 

[John Hartwell]

In the U.S. Regular Army, as I understand it, an Assistant Surgeon could be a captain, a full Surgeon a major. A lieutenant colonel would be a medical inspector, a colonel would be an assistant surgeon-general or the medical inspector-general, and a brigadier general would be the Surgeon-General of the Army.

For Volunteers, it was apparently the same for Surgeons and Assistant Surgeons. But what about Chief Surgeons of brigades, divisions or corps?

 

[Sowbelly and Hardtack]

There are a couple of regimental surgeons who were promoted to Lieutenant Colonel. Dr. Alexander Augusta was promoted to LTC. of the 7th USCT in March 1865.

Remembering Dr. Alexander Augusta, the U.S. Army’s First Black Doctor

Dr. Alexander Augusta was the first African American to be an Army doctor.

www.health.mil

While I'm not an expert on Civil War regulations, the short answer to your original question is "No", a Chief Surgeon could not and still can't take tactical field command of a unit in combat. So far I have found no example of this happening during the Civil War or in conflicts since.