which was did he take part in?
World War I - he rejoined Battery B, successfully recruiting new soldiers for the expanding unit, for which he was elected as their first lieutenant.
Harry S. Truman
When the United States entered World War I, Truman rejoined Battery B, successfully recruiting new soldiers for the expanding unit, for which he was elected as their first lieutenant. Before deployment to France, Truman was sent for training to Camp Doniphan, Fort Sill, near Lawton, Oklahoma when his regiment was federalized as the 129th Field Artillery. The regimental commander during its training was Robert M. Danford, who later served as the Army's Chief of Field Artillery. Truman later said he learned more practical, useful information from Danford in six weeks than from six months of formal Army instruction, and when Truman later served as an artillery instructor, he consciously patterned his approach on Danford's.

Truman also ran the camp canteen with Edward Jacobson, a clothing store clerk he knew from Kansas City. Unlike most canteens funded by unit members, which usually lost money, the canteen operated by Truman and Jacobson turned a profit, returning each soldier's initial 
who was the president for most of the 1950s Dwight David "Ike" Eisenhower  served as the 34th president of the United States from 1953 to 1961. who is harry s. truman? 33rd president of the United States from 1945 to 1953 where was he born? Lamar, Missouri
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Harry S. Truman [SEP] World War I
When the United States entered World War I, Truman rejoined Battery B, successfully recruiting new soldiers for the expanding unit, for which he was elected as their first lieutenant. Before deployment to France, Truman was sent for training to Camp Doniphan, Fort Sill, near Lawton, Oklahoma when his regiment was federalized as the 129th Field Artillery. The regimental commander during its training was Robert M. Danford, who later served as the Army's Chief of Field Artillery. Truman later said he learned more practical, useful information from Danford in six weeks than from six months of formal Army instruction, and when Truman later served as an artillery instructor, he consciously patterned his approach on Danford's.