About familytreegirl
Shelley Murphy, aka “familytreegirl”, a native of Michigan residing in Central Virginia, Shelley has been an avid genealogist for over 25+ years researching the Davis, Marsh, Goens/Goins/Goings, Roper, Boyer, Worden, Cureton, and Murphy family lines. She is a Coordinator and faculty for the Midwest African American Genealogy Institute (MAAGI), presents Genealogy 101 workshops at the local community college, state and national genealogy conferences. She holds a Doctorate of Management in Organizational Leadership and works as an adjunct professor for Averett University.
Murphy is known for her inspiring and interactive “Getting Started” Methods and Strategies for genealogy research, “Time and File management” along with interesting problem-solving methodology lectures. Shelley currently has 20+ publications with Charlottesville Genealogy Examiner and the Central Virginia Heritage, a publication of the Central Virginia Genealogical Association. She is an instructor for the Midwest African American Genealogy Institute (MAAGI).
Doctor of Management in Organizational Leadership, Adjunct Professor, Professional Genealogist. Volunteers for American Red Cross as a Disaster Services Instructor, facilitates financial education workshops for the last 8 years, and former licensed Real Estate Broker
This 32-page guide by Reginald Washington (now retired from the National Archives)
Family Tree Girl 
I have an instance of a (light-colored) black man becoming part of a (white) Indiana regiment in the Mexican-American War. I think this might be a “first” or at least highly unusual. Any ideas how I can determine this?
I am not sure I get what you are saying but if you are saying that a light skinned black man passed for what, I get it. But I would not be surprised.
I would like to know more
He wasn’t passing. He was known as a black man. He served as a cook for a company in the 5th Indiana Volunteers in the Mexican War. The men in the company were paying him out of their pockets. When they were in Mexico, they petitioned their superiors to enlist him, which was done in Mexico City on Dec. 31, 1847 (confirmed on the adjutant general’s roster). After he mustered out, he received bounty land in Indiana (confirmed in bounty warrants and BLM land records). After that, I don’t find any records I can be sure of. He is in Indiana in 1850, listed as Mulatto in the census.