During the American occupation, in 1907, part of it was selected for the establishment of a government agricultural school—the present-day Central Luzon State University (CLSU).

On October 18, 1912, Newton W. Gilbert, the island's acting Governor General, issued Executive Order No.

The Japanese defense had eight strong points around the area, including that at Muñoz, which was ordered attacked by Gen. Innis Swift, commander of the I Corps, to the 6th Division.

[12] Filipinos also engaged the Japanese in a close-quarter battle—the battle of Muñoz—including Col. Cesar Pobre, a member of the United States 98 Mortar Brigade.

Muñoz had its territory reduced on January 1, 1948, when barrios Alula, Calisitan, and Saverona were separated and, along with portions of Cuyapo, Guimba, and Lupao, were organized into the province's twenty-eighth municipality—Talugtug—by virtue of Executive Order No.

[14] In late September of that year, a ten-hour battle, one of the bloodiest between the Philippine Constabulary (PC) and the Hukbalahap, occurred near the municipality where 83 people were killed.

[15] During the Marcos administration post-martial law, Jun Quimpo, an activist who had been working for an underground movement in the rural areas, was fatally shot by his former comrade who had surrendered to the PC, in Calisitan in December 1981.

[6][18][19] This is due to the presence of various centers of excellence and research and development agencies;[18] at the time of the cityhood, there were sixteen, most notably the CLSU, Philippine Rice Research Institute, Philippine Carabao Center, as well as the provincial offices of the DOST and the Agricultural Training Institute.

[6] On December 9, the conversion was ratified in a plebiscite with about 12,468 voters favoring the bid, against 602 who voted against; hence becoming the province's fourth component city,[19] officially bearing the name Science City of Muñoz[18][19]—the only local government unit in the country holding such designation to date.

Churches: Poverty Incidence of Muñoz Source: Philippine Statistics Authority[31][32][33][34][35][36][37][38] There are many new establishments in Munoz in the past few years.

In terms of commercial and shopping sector, Robinsons, Savemore and Puregold has also initially identified locations in the city for future construction.

With a bustling market center with rice trading as a major economic activity, it has transformed into its present status as a Science City by virtue of Republic Act 8977 on December 9, 2000.