It is very rare that you'll find information written about African-American women's roles in every war effort in U.S. history. Until recently, knowledge of their heroic contributions was severely limited, but that has changed since Indiana-based Buffalo Soldiers Research Museum unveiled pictures and information about the women.

" They endured physical discomfort and personal criticism, while many of their contributions were unrecognized and unrewarded. They placed themselves in danger's path - offering their abilities and strengths to preserve values and ensure freedom," wrote S.A. Sheafer in the book "Women in America's Wars."

Inspired by the promise of freedom from slavery, some women courageously worked as spies during the Revolutionary War. Others, as narrated by former slave-turned-author Lucy ­Terry, disguised themselves as men and fought side by side with them against the British. In the Spanish-American War and World War I, black women served valiantly as nurses and in other support roles. A list of the women and their contribution(s) are listed below.

Harriet Tubman

Served as a Union spy , volunteer nurse, and armed scout. Because of her various contributions, she reportedly acquired the name "General Tubman" from soldiers.

Susan Taylor King

Another former slave, joined the all-black First South Carolina Volunteers unit as a nurse, and later started a school for children and soldiers.

Cathay Williams

After being freed from a Missouri plantation, Williams was pressed into service during the Civil War by Union forces. Williams signed up for service in November 1866, giving her name as William Cathay and passing as a man. Before falling ill and having her gender revealed, Williams served as a Buffalo Soldier with the 38th U.S. Infantry Regiment for two years - more than 80 years before women were allowed to officially enlist in the peacetime Army.

Maj. Charity Adams

The first black officer of the Women's Army Corps (WAC) during World War II. Adams commanded the first all-black female unit, the 6888th Central Postal Directory Battalion. " Every single piece of mail that went to Europe passed through this postal battalion," said filmmaker Frank Martin, whose 2010 documentary, "For Love of Liberty: The Story of America's Black Patriots," lauds the service of Maj. Adams' 855-member battalion. Maj. Adams spent the last year of the war clearing backlogs of mail, first in Birmingham, England, and then Rouen, France.

Army Nurse Corps Maj. Marie Rogers

Maj. Rogers was awarded the Bronze Star by President Lyndon Johnson for distinguished service. In 1948, the dynamics of black women in the military changed when President Harry Truman signed the Women's Armed Services Integration Act, which permitted women to join the regular Army and later issued Executive Order 9981, which ended segregation in the military. Following Truman's executive order, an increasing number of African-American women - volunteers, mostly nurses - served in Vietnam.

Diane Lindsay

Was the first black female nurse to receive the Soldier's Medal of Heroism. She was later promoted to captain. Lindsay was of the 95th Evacuation Hospital.

Lt. Phoebe Jeter

Ordered her all-male platoon to fire a battery of Patriot missiles at incoming Iraqi Scud missiles, downing at least two of them. It was the first and only such feat by a female officer in the war.

U.S. Navy Vice Adm. Michele Howard

The first African-American woman to command a Navy combat ship, made news in 2009 when it was involved in the rescue of the merchant ship Maersk Alabama's captain from Somali pirates.

" It is clear to all of us that women are contributing in unprecedented ways to the military's mission of defending the nation," said Defense Secretary Leon Panetta in January, when he lifted a ban preventing women from serving in combat. " They serve, they're wounded and they die right next to each other. The time has come to recognize that reality. " Today, black women are well represented in the armed forces. An estimated 40% of the 35,000 women active in Operation Desert Storm were African-Americans.

Maria Lloyd (@WritingsByMaria) is the Business Manager for the Your Black World Network and Dr. Boyce Watkins. She is a graduate of Clark Atlanta University and an advocate of dismantling the prison industrial complex, increasing entrepreneurship, reforming education, and eradicating poverty.