Walter Krueger was an American soldier and general officer in the first half of the 20th century. He commanded the Sixth United States Army in the South West Pacific Area during World War II. He rose from the rank of private to general in the United States Army.
Born in Flatow, West Prussia, German Empire, Krueger emigrated to the United States as a boy. He enlisted for service in the Spanish–American War and served in Cuba, and then re-enlisted for service in the Philippine–American War. He was commissioned as a second lieutenant in 1901. In 1914 he was posted to the Pennsylvania Army National Guard. His regiment was mobilized on 23 June 1916 and served along the Mexican border. After the United States commenced hostilities with Germany in April 1917, Krueger was assigned to the 84th Infantry Division as its Assistant Chief of Staff G-3, and then its chief of staff. In February 1918, he was sent to Langres to attend the American Expeditionary Force General Staff School, and in October 1918, he became chief of staff of the Tank Corps.
Between the wars, Krueger served in a number of command and staff positions, and attended the Naval War College at his own request.