In 1917, the United States was drawn into the struggle, partly to support democracy and partly to maintain the maritime rights of neutral nations. The call was answered by thousands of Iowans, many having served on the Mexican border.
The first Iowa National Guard unit to be sent to France was the 168th Infantry. The 168th Infantry was a consolidated force made up of three prewar regiments of Iowa National Guard infantry. It was assigned to the 42nd ‘Rainbow’ Division, one of the first American divisions to reach Europe. The 42nd Division took part in engagements at Baccarat, Esperance-Souaine, Champagne-Marne, Essey-Pannes, and the final great Allied offensive at Meuse-Argonne. Brigadier General Douglas MacArthur was the Chief of Staff of the 42nd Division. Speaking to a French major, he said, ‘Is it any wonder that my father was proud of this regiment.’ The 168th, as the 51st Iowa, had served under the elder Arthur MacArthur in the Philippines.
The remainder of the Iowa National Guard forces that were mobilized for World War I were assigned to the 34th Division. These Iowans went to Mexico to train in the desert. They took as their insignia a white bovine skull superimposed upon a black Mexican water jug. The 34th earned the name ‘Sandstorm’ because of the omnipresent sand in food and clothing. The 34th left for Europe on September 17, 1918. Upon their arrival in France, the division experienced a bitter disappointment. Instead of going into battle as a unit, they were used as a replacement pool.
Back home, the Iowa National Guard training site at Camp Dodge was greatly expanded and functioned as one of 16 regional training sites for the United States Army . . .”
There is a page dedicated to World War I, as part of the history section.
The Champagne-Marne offensive was one of the most decisive battles of the World War I. Fought over a four-day period (July 15-18, 1918), it was a daring attempt by the German General Staff to drive a wedge between the British and the French and end the war before the bulk of American forces could arrive in France. Several American divisions already in France, including the 42nd, played an important role in stopping the German attack. As one soldier of the 168th wrote, ‘By noon of July 15, the German offensive had been halted, but both sides maintained a terrific artillery duel until the 18th.’
‘Life around our part of the country was an inferno, with earth quaking from the shock of artillery, and the sun blotted out by the dense clouds of gray-black smoke.’”
Some background on the expansion of Camp Dodge, and the time after the official declaration of war in April, is also available and a good source for information.