Bell was a major general in the Regular United States Army, commanding the Department of the East, with headquarters at Governors Island, New York at the time of his death in 1919.

Bell became notorious for his actions in the Philippine–American War, in which he ordered the detainment of Filipino civilians in the provinces of Batangas and Laguna into concentration camps, resulting in the deaths of over 11,000 people.

In 1874, after two years of working in a general store,[3] Bell sought a military career, and secured appointment to West Point, where he eventually graduated 38th in a class of 43.

At the outbreak of the Spanish–American War, Bell was a first lieutenant acting as adjutant to General Forsyth, then commanding the Department of the West, with headquarters at San Francisco.

[5] In 1925, Bell was posthumously awarded the Distinguished Service Cross for having conducted detailed reconnaissance of Fort San Antonio Abad on August 10, 1898.

[9] In 1900, a short documentary film debuted by American Mutoscope & Biograph of Bell's driving a pack of mules across the Agno River.

In response to guerrilla attacks by general Miguel Malvar, Bell implemented counterinsurgency tactics, destroying crops and slaughtering livestock in order to starve insurgents into submission.

[11] Living conditions in the camps were poor, with inadequate sanitation leading civilians to fall ill with a multitude of diseases, including cholera, smallpox, beriberi, and bubonic plague.

[16] Bell's tactics mirrored similar civilian reconcentration policies previously carried out by the Spanish in Cuba and by the British in South Africa during the Second Boer War.

According to a legal brief written for the United States Senate Committee on the Philippines in 1902 by Julian Codman and Moorfield Storey of the American Anti-Imperialist League, Bell said in an interview with The New York Times on May 3, 1901, that one-sixth of the population of Luzon had been killed or died of dengue fever in the previous two years of war.

The 4th Division remained in Texas City as reserve and, although at several times he seemed about to cross the Rio Grande, he was never a part of the Mexican expeditionary force.

Bell's aide, Captain George C. Marshall, was most directly involved in the logistical support for these camps, battling a lethargic army supply system to properly equip the volunteer citizen soldiers.

In the same month, Bell was offered and promptly accepted the command of the 77th Division of the National Army, to be organized at Camp Upton, New York.

Bell commanded the division when the first newly appointed officers climbed the hill and reported to their first assignment, through that formative stage when barracks were thrown together at a miraculous speed, and being filled at the same rate.

United States Military Academy Cadet – class of 1878 On January 5, 1881, Bell married Sarah Buford (April 28, 1857 – December 22, 1943) at Rock Island, Illinois.