On 24 December 1898, the Spanish forces under the command of General Diego de los Ríos evacuated Iloilo[1]: 511  and the Filipino flag was raised on Christmas Day.

As the military governor of the province and General-in-Chief of the army, he challenged the American forces led by General Hughes using guerrilla tactics.

Eventually, leading citizens of Iloilo wrote a circular urging General Delgado to surrender for the benefit of "the victims of useless resistance.

He was recognized by the Americans as "the ablest leader" on the island and appointed as the first Governor of Iloilo province upon the establishment of the civil government on 11 April 1901.

In 2019, an equestrian statue of Delgado, made by Spanish Sculptor Ginés Serrán-Pagán, was also erected in front of the Casa de Emperador at the Iloílo Business Park.