Benjamin Oliver Davis Sr. (July 1, 1877 – November 26, 1970) was a career officer in the United States Army. One of the few black officers in an era when American society was largely segregated, in 1940 he was promoted to brigadier general, the army's first African American general officer.

A native of Washington, D.C., Davis attended M Street High School, where he obtained his first military experience by participating in the school's corps of cadets program. During his senior year, he also enrolled in courses at Howard University, which enabled him to play on the school's football team. After his 1898 graduation, Davis served briefly as a second lieutenant in the District of Columbia National Guard before joining the 8th U.S. Volunteer Infantry for the Spanish–American War and receiving his commission as a first lieutenant. After the war, Davis was discharged from the volunteers and joined the regular army as a private. He soon became a non-commissioned officer, and in 1901 passed the commissioning exam and received appointment as a second lieutenant of Cavalry.

Davis served in the Philippine–American War and World War I, in which he demonstrated noteworthy leadership and administrative ability, but found himself frequently shunted to less than desirable assignments as his career progressed. In addition to receiving less prestigious assignments such as professor of military science at historically black colleges because of segregation in the army, as one of only a handful of black officers he also experienced delays in promotions and disapproval of recommendations for professional education such as the United States Army Command and General Staff College. Despite these challenges, Davis worked within the army's white hierarchy to attain a record of superior technical and tactical proficiency as he slowly rose through the ranks. He was promoted to colonel in 1930, and commanded the New York National Guard's 369th Infantry Regiment (later the 369th Anti-Aircraft Artillery Regiment) from 1938 to 1940.

Though he was near retirement, political considerations during the 1940 United States presidential election, the need to obtain the support of black citizens for U.S. involvement in World War II and Davis's own long record of accomplishments led to his promotion to brigadier general. He commanded 4th Cavalry Brigade, 2nd Cavalry Division during its organization and training, and also served as acting division commander. He attained the mandatory retirement age of 64 in 1941, but remained on active duty to perform wartime inspections of black units and offer observations and recommendations on policies including racial integration.

Davis retired in 1948 and resided in Washington, D.C. He was a member of the American Battle Monuments Commission from 1953 to 1961. Davis later moved to Chicago to reside with one of his daughters. He died at Great Lakes Naval Hospital on November 26, 1970. Davis was buried at Arlington National Cemetery. Davis's children included Benjamin O. Davis Jr., the first black general in the United States Air Force.

Early life and education Davis said he was born in Washington, D.C., on July 1, 1877, the third child of Louis P. H. Davis and Henrietta (née Stewart) Davis. Called "Ollie" as a boy, he was raised in the LeDroit Park neighborhood of Washington and attended the Lucretia Mott School.

Davis attended M Street High School in Washington, where he played baseball and football, and was captain of the football team. He also participated in the cadet program, in which city high schools organized military units that competed against each other in marksmanship, drill and ceremony, and other soldier skills. Davis attained the rank of captain as commander of Cadet Company B. During his senior year of high school he took courses at Howard University and played on the school's football team. His father, a messenger for the Interior Department, and his mother, a nurse, urged him to enroll in college after high school.

Early career While in high school, Davis received his commission as a second lieutenant in the District of Columbia National Guard's Company D, 1st Separate Battalion. After graduating from high school in 1898, Davis planned to enter full-time military service. He applied for admission to the United States Military Academy, and his father hoped the contacts he had made in his government position would enable him to secure an appointment through President William McKinley's administration, but the senior Davis was informed that appointing a black cadet was not feasible at that time.

In June 1898, Captain Jesse M. Lee of the 9th United States Volunteer Infantry Regiment, an African American unit raised for the Spanish–American War, recruited Davis and considered him for an officer's commission. Davis passed the required physical exam, but Lee withdrew his offer because of Davis's youth. He subsequently offered Davis a non-commissioned officer's appointment, which Davis rejected. Captain Robertson Palmer, a white officer in the African American 8th U.S. Volunteer Infantry, subsequently offered Davis a commission if Davis helped him recruit the sixty soldiers necessary to man the company Palmer was slated to command. Palmer and Davis quickly recruited their company, and on July 13, 1898, Davis was commissioned as a first lieutenant in the 8th U.S. Volunteer Infantry's Company G. He was soon appointed as his battalion's adjutant, in addition to duty as officer in charge of prisoners awaiting court-martial, and was stationed at Fort Thomas, Kentucky, and Chickamauga Park, Georgia, from October 1898 until the regiment was disbanded in March 1899.

Davis was mustered out of the United States Volunteers on March 6, 1899. His parents hoped he would attend college, but on June 18, 1899, he enlisted as a private in Troop I, 9th Cavalry Regiment. Assigned to Fort Duchesne, Utah, he served first as the troop's clerk and later as the 3rd Squadron's sergeant major. Davis later recounted that among his reading was Three Roads to a Commission in the U.S. Army by William P. Burnham, which included details on being commissioned from the ranks, so he continued to pursue his ambition of becoming a regular army officer. In late 1900, Davis's unit was commanded by Lieutenant Charles Young, one of a handful of African American officers serving in the U.S. military at that time. Young encouraged Davis and tutored him in the subjects covered on the officer candidate test, especially mathematics, which had been Young's weakest subject while a student at the United States Military Academy. In early 1901 Davis passed the physical exam and the battery of tests that were administered at Fort Leavenworth. On February 2, 1901, Davis was commissioned a second lieutenant of Cavalry.

In the spring of 1901, Troop I was posted overseas to serve in the Philippine–American War. In August 1901, Davis assumed officer's duties when he was assigned to Troop F, 10th Cavalry. Davis spent a year on the island of Panay as his new regiment fought Filipino insurgents. In September 1901, Troop F was split into separate detachments, with Davis being placed in charge of approximately 25 men who garrisoned the town of Lambunao. While in the Philippines, Davis demonstrated an innate ability to learn foreign languages by becoming fluent in both Spanish and the local Visayan language. He received an "excellent" rating on his first officer evaluation report, and his regimental commander, Colonel Samuel Whitside, later told Davis that several of the regiment's white officers thought so highly of him that they attempted to have him assigned to their units. While Davis was not known for developing personal or emotional bonds with his soldiers, they still regarded him highly, with most describing him as stern with respect to military discipline, but well liked.

Troop F returned to the U.S. in August 1902, and Davis was stationed at Fort Washakie, Wyoming, where he also served for several months with Troop M. He subsequently served as regimental adjutant and commander of several details that performed special duties, including ordnance, engineering, signal, and recruiting. Davis also led several hunting parties on which the garrison relied to supplement their food rations. In organizing hunting parties, Davis endeavored to ensure that each soldier got to participate at least once in order to train them on soldier skills including tracking and land navigation. As Davis's service in Wyoming continued, his additional duties included at different times post exchange officer, civilian education officer for enlisted men, and adjutant, quartermaster, and commissary of the Fort Washakie post. He consistently excelled in these assignments, with his efficiency reports routinely indicating his superior management and administrative abilities. Davis also participated in professional development activities including study of the Cavalry Drill Regulations and Small Arms Firing Regulations, in which he attained such a high level of proficiency during instruction that he was exempted from final testing.

Continued career Davis was promoted to first lieutenant on February 28, 1905. In April 1905, he was assigned to the 10th Cavalry Regiment at Fort Robinson, Nebraska. In September 1905, Davis was assigned as professor of military science and tactics at Wilberforce University, a traditionally black institution of higher learning. Davis disliked the assignment because Wilberforce was a Methodist institution, and he was not religious. When the school's president, Joshua H. Jones, questioned Davis's absence from church on the first Sunday after arriving at Wilberforce, Davis stated that he had no intention of attending. He also told Jones that if he was unhappy about Davis's decision, he should request Davis's reassignment, since Davis preferred to serve with his regiment.

Davis and Jones continued to quarrel, with Davis violating protocol through activities including keeping alcoholic beverages in his home, and Jones refusing to allow Davis to teach military science more than three hours per week. The dispute eventually reached the United States Department of War, where investigating officers concluded that Davis had legitimate complaints, but that many of the problems between the two men stemmed from Davis making "excessive demands" of Jones. Davis's additional duties while at Wilberforce including serving as the regular army inspector and evaluator of training for the District of Columbia National Guard's 1st Separate Battalion. Davis visited the battalion annually during its summer training period so he could provide instruction, supervise training, and inspect readiness. D.C. National Guard leaders appreciated Davis's attention and proficiency, and continued to solicit the War Department for his support. As a result, his assignment at Wilberforce and his additional duty with the 1st Separate Battalion were extended for a year after he had completed the usual three-year tour in 1908.