In 1914 the National Guard for Kansas, Nebraska, Wyoming, Missouri and Colorado comprised the 14th Military District designed to form a single tactical division in the event of deployment for war. Nebraska would furnish Infantry Regiments 3 and 4 with Broken Bow being Company I, 4th Infantry Regiment. At that time a Regiment was formed as a Headquarters and Band, with Companies designated A through M.
This is Camp Funston Kansas in 1918, filled with Guard units training for deployment in the Great War.
 
In the war with Spain in 1898, the Nebraska Guard supplied 3 regiments one to the Phillipeans, one to Cuba and one to Georgia as a stategic reserve. All units took significant casualties to disease. In 1904 it was still 3 regiments strong, nearly 2000 men and an officer corps of 116. At this time the only Federal troops in Nebraska were garrisoned in Ft Valentine and Ft Robinson for indian control and at Ft Crook near Omaha. The last significant Souix uprising was in 1891 and required the Nebraska Guard to respond.
 
Notice the intensity of training shown in this picture below from the 1908 Nebraska Guard camp at Ashland, where the farm boys practice shooting on the range. I would guess from looking at the picture, this platoon of men only had one working rifle to train with. It is likely that the old black powder Civil War design single shot M1888 is what the Guard used in the war with Spain. The 5-shot Springfield M1906 that would fight in the Great War had just gone into production. When I started ROTC in 1966, we were still training with 1906 Springfield rifles, the same as in the photo!
The Springfield rifle was essentially a copy of the German Mauser 1893 model, so much so that the US eventually paid a patent claim to Germany for the 1 million rifles made to defeat them. However, Germany made its machine guns under license from Hiram Maxim and they had to pay patent fees to England for the privilage of using them with great effect against her troops.