Born in Baltimore, Maryland, on July 3, Williams enlisted in the U.S. Marines upon graduating high school in 1974. He took basic training at Parris Island, South Carolina, where he was promoted to platoon guide.
After basic training, he was sent to the Desert Warfare Training Center at Twenty-nine Palms, near Palm Springs, California.

While at Twenty-nine Palms, his superiors became impressed with his leadership skills, and he was recommended for, and accepted to, the Naval Academy Preparatory school at Newport, Rhode Island. He completed the one-year course, and was accepted to the U.S. Naval Academy at Annapolis.

07.03.1956 LCDR Montel WilliamsB

When he arrived at Annapolis on July 6, 1976, he was honorably discharged as a corporal from the marines, and enlisted into the navy as a midshipman. While at Annapolis, Williams studied Mandarin Chinese and graduated with a degree in general engineering and a minor in International Security Affairs. It was at Annapolis that Williams first began to shave his head. Upon his graduation in 1980, he became the first black enlisted marine to complete and graduate both the Academy Prep School and Annapolis.

Commissioned an ensign, he spent the next one and a half years at Naval Security Group Detachment (NSGD) Guam as a cryptologic officer, where he served at sea and ashore. In 1982 he was transferred to Defense Language Institute in Monterey, California, where he studied the Russian language for one year. In 1983 he was transferred to Naval Security Group Activity (NSGA) Maryland at Ft. Meade, Maryland, where he worked with the National Security Agency. What Williams did there is vague, due to the sensitive nature of the work, but he performed various intelligence missions. He also served afloat during the invasion of Grenada.

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After three years deploying as a Direct Support Officer at Ft. Meade, Williams, now a lieutenant, moved to the Naval Security Fleet Support Division as the division officer. It was while counseling his crew that he discovered a gift for public speaking. In 1988, he began conducting informal counseling for the wives and families of the servicemen in his command. He was later asked to speak to a local group of kids in Kansas City, MO about the importance of leadership and how to overcome obstacles on the road to success — thus beginning a three-year career in motivational speaking.

Williams traveled the country talking to more than three million teenagers nationwide and gave up his naval commission to pursue speaking full-time. He left the navy with the rank of lieutenant.  He received the Meritorious Service Medal, Navy Commendation Medal and Navy Achievement Medal. In addition, he reached out to thousands of parents, educators and business leaders, encouraging them to work together to address youth issues, trends and to inspire youngsters to reach their highest potential. These efforts to reach out to the community eventually lead to the Montel Williams Show on television.

Source: military.com