In August 1898, Ward volunteered for
Spanish–American War service and successfully applied for a
second lieutenant's commission in the 109th New York Infantry Regiment, a unit that was raised to perform state duties while other National Guard units were mobilized for federal service. In January 1899, he was assigned to the 9th Infantry Regiment, and later that year he received promotion to
first lieutenant. In 1901, Ward commanded a company during the National Guard's response to a streetcar worker's strike in
Albany. In 1902, Ward was promoted to
captain, and in 1907 he received promotion to
major. In 1908, the 9th Infantry was transferred to the
Coast Artillery Corps; Ward became an authority on Coast Artillery, which resulted in his appointment as a member of the state examining board for Coast Artillery officers. In 1912, Ward was appointed to the staff of the
27th Division and promoted to
lieutenant colonel. The division was activated for federal service in 1916 as part of the US response during the
Mexican Border War. Ward was sent to Texas in advance of the division's main body, and planned and organized administrative and logistics details including bivouac sites and food and water. During the division's border service, Ward was assigned as assistant chief of staff. One Ward initiative while in Texas was organizing a weekly newspaper,
The Rio Grande Rattler, and he became its managing editor. The paper was published in
Mission, Texas, and by using professional journalists assigned to the division to produce high-quality stories, the
Rattler developed a large subscriber base both in the
Lower Rio Grande Valley and in New York state. ==Continued career==