The Alexandria Light Infantry was formed in 1878 as a local militia unit. The unit, which was a private organization at that time, owned an armory at 200 South Royal Street. Under the Dick Act of 1903, all local militias were incorporated into the National Guard, and the president was given the authority to federalize them in emergencies. When Pancho Villa raided Texas in early 1916, the federal government decided to launch a punative expedition across the border. President Wilson exercised the authority to federalize the National Guard for the first time in order to provide border security while the regular army was in Mexico. The mass mobilization of the National Guard and deployment to the Mexican border also served as an important dress rehersal for America's mobilization for World War I.
The Virginia Volunteers reorganized several times between 1878 and 1916. By 1916, the Alexandria Light Infantry was Company G of the 1st Virginia Infantry Regiment. When the call for mobilization came, the city turned out to bid their militia a farewell. On 28 June 1916, a procession of city officials, dignitaries and even two veterans of the 1846 war with Mexico marched to the armory and escorted the troops to the train waiting for them on the siding at Fayette and Cameron Streets. Last minute enlistments brought the membership of the Alexandria Light Infantry up to 90 people, and recruiting continued after their departure for Richmond. After review in Richmond (during which several soldiers were dismissed as physically unfit), the entire Regiment deployed to area around Brownsville, Texas, to patrol the border and practice a variety of military drills, including trench warfare which had become prevelant in Europe.
On the eve of the company's departure, the city also took over ownership of the armory and assumed the mortgage for it. The city assumed responsibility for several repairs and upgrades and began using the drill space as a public basketball and volleyball court when not in use for military purposes. In 1941, the armory served as a USO center, but it was destroyed by fire in 1953. Today, the Armory Tot Lot stands on the site.
The deployment to Texas was relatively uneventful, and the troops returned home by January 1917. However, only six months later, the National Guard was again mobilized after America joined the war in Europe. Lessons learned during the deployment to the Mexican border were applied to the mobilization for World War I. The 1st, 2nd and 4th Virginia Infantry Regiments were reorganized into the 116th Infantry Regiment of the 29th Division, and the veterans of the border deployment applied the skills they learned there to the Meuse-Argonne Offensive.