ILAGAN, a municipality (with administration centre and 57 barrios or districts), and capital of the province of Isabela, Luzon, Philippine Islands, on an elevated site at the confluence of the Abuluan and Cagayan rivers, about 200 m. N.N.E. of Manila. It was formerly included in the province of Nueva Ecija. Pop. (1918), 23,279. The surrounding country is the largest tobacco growing region in the Philippines. Considerable corn is also raised. In 1918, it had 7 manufacturing establishments with output valued at 44,90o pesos. Of the 21 schools, 19 were public. The language spoken is Ibanag.