Ben Lear was born in Hamilton, Ontario on May 12, 1879. His military service began in 1898, when he enlisted with the 1st Colorado Infantry, USV, for the Spanish-American War as a First Sergeant. He was promoted to second lieutenant during the Philippine-American War in the 1st Colorado and later in the 36th Infantry, USV, but joined the regular army as a sergeant at the end of the war. He subsequently served in World War I.
He was a 1912 Olympian, part of the equestrian team which won the Bronze Medal in the three day team event.
Lear graduated from the Army School of the Line in 1922, the Army General Staff School in 1923, and the Army War College in 1926. He was promoted to Brigadier General in May 1936 and Major General]] in October 1938. He commanded the 1st Cavalry Division from 1936 to 1938, and the Pacific Sector of the Panama Canal Zone from 1938 to 1940.
He was commanding general of U.S. Second Army from October 20, 1940 to April 25, 1943 and was promoted to temporaire lieutenant general in October 1940. As such, he was responsible for training a large number of U.S. soldiers during World War II. He became known as a strict disciplinarian.
It was in the lead-up to these maneuvers that Lear acquired the nickname "Yoo-Hoo". He was playing golf at the Country Club in Memphis, Tennessee in civilian clothes on Sunday, July 6, 1941, when a convoy of 80 U.S. Army trucks carrying men of the 35th Division rolled past. The troops in the passing trucks subjected a group of women in shorts to a series of whistles and "lewd and obscene" catcalls. Lear had the convoy stopped and told the officers that this conduct was unacceptable, and they had disgraced the army. Lear's punishment was to make every one of the 350 men in the convoy march 15 miles (24 km) of the 45 mile (72 km) trip back to Camp Joseph T. Robinson, Arkansas in three 5 mile sections. This they did in the 97°F (36C) heat. Many men straggled and a number collapsed. There was storm of public criticism of Lear's action from people who felt that the soldiers had been harshly and collectively punished when they had done nothing wrong. The commander of the 35th Division, Major General]] Ralph E. Truman was well-connected politically, his cousin being Senator Harry S. Truman, and some Congressmen called for Lear to be retired. However, to Army eyes this was not a case of sexual harassment but of indiscipline, and no action was taken against Lear. The derogatory nickname "Yoo-Hoo" stuck.
During the Louisiana Maneuvers, Lear led his U.S. Second Army against the U.S. Third Army under Lieutenant General Walter Krueger. In these maneuvers, Lear judged the control and discipline of the 35th Division to be unsatisfactory and relieved Truman of his command.
Lear did retire in May 1943, but was immediately recalled to active duty to serve on the Personnel Board of the Secretary of War, and promoted to Lieutenant General. On the death of Lieutenant General Lesley J. McNair in Normandy in July 1944, Lear became Commanding General of Army Ground Forces. After the German counter-attack in the Ardennes, caused a manpower crisis, he was appointed Deputy Commander of European Theater of Operations, US Army, responsible for Theater Manpower. As such, he overhauled the replacement system, but the war against Germany ended before the full benefits of his reforms could be realised.
He retired again in July 1945, but was promoted to General on July 19, 1954 by special Act of Congress (Public Law 83-508). He died at Murfreesboro, Tennessee on November 2, 1966, and was buried in Arlington National Cemetery, Section 4, Grave 2690.