Alegria was originally known as Sitio Anahaw founded by Pablo Ugay, Ciriaco Efren, Vicente Ugay, Agripino Murcilla, Pio Odvina, Bernardo Orquina, Fermin Odchimar who among others migrated from the Municipality of Bacuag, Surigao del Norte. Because of her location, near Lake Mainit, it was always over- flooded during rainy season prompting the people to transfer to a safer place now known as Poblacion Alegria.

The name Alegria was derived from the Spanish word “Alegre” which means lively. This was given by Judge Sixto Olga who happened to pass the night in the place. He was offered by the residents with party and dance. Amused by the affair, Judge Olga advised the people to change the name Anahaw to “ Alegria”.

By virtue of Republic Act No. 5239 dated June 15, 1968, Alegria was separated from the town of Mainit, thereby making it as independent municipality.

Tomas V. Cosca, an Ilongo of Pilar, Capiz, was the first Mayor of Alegria from 1968 – 1971. He was succeeded by a Boholano Francisco M. Bagol who reigned this town from 1971 to December 1979. An ex-veteran of USAFFE, Pedro A. Umipig of Ilocano origin, became the third Chief Executive of Alegria. He served from 1980 up to 1984 only due to his failing health that caused him to retire early. By virtue of the law of succession, Vice – Mayor Ricardo R. Escalante took over as Mayor until the upshot of Edsa Revolution in 1986. On April, 1986, the Revolutionary Government of President Corazon C. Aquino installed Ruben O. Zamora as Officer– In–Charge in the local government of Alegria.

Zamora governed for 12 consecutive years until he retired after completing the 3 consecutive terms, (1986-1998) as mandated by RA 7160.

From July, 1998 up to June 30, 2007, Dr. Jessie U. Aguilera, the second local chief executive in the history of politics that graduated and finished her three consecutive terms also. There were development efforts during her administration in terms of health, social services and water system development. She started to adopt the computerization program in the municipal government which drive minimal linkage of network and services with local offices and national government agencies.

In July 2007, the Municipality of Alegria is honored to have a brilliant, dedicated, a religious leader and dynamic Local Chief Executive in the person of Hon. Mayor Dominador G. Esma, Jr. An experience fellow in family business and in private sector. His dreams and aspirations is to uplift the position of the LGU to be true partners of progress and development among different sectors and stakeholders of the community towards efficient delivery of basic services, improved resource and financial system and a transparent governance. He started promoting the municipality with cultural celebration called as “Kabibo” Festival, showcasing the cultural dance presentations and local and traditional products like rice coffee (kape), rice cake (bingka), and a rice dish rolled in banana leaves (bodbod). His administration able to build public market, integrated transport terminal, and started building the new municipal hall. After serving his full three consecutive terms as the Municipal Mayor, his young brother Engr. Rene G. Esma continued the Esma legacy in the public service as the Municipal Mayor in July 2016.

Mayor Rene G. Esma, a Mechanical Engineer by profession, became the eight Local Chief Executive in the municipality after serving for many years as Overseas Filipino Worker with various managerial positions in the foreign industries. From his experiences in the foreign country, Mayor Rene Esma brings home with his dream for wealth and progress in the municipality. His administration completely build the new municipal hall, the municipal gymnasium called Don Francisco “Kikoy” Bagol Sports Complex, the new public market, among others that served as the iconic landmark of the municipality.

Today, the Municipality of Alegria, Surigao del Norte, continue aspire to reach the dream of the recent Local Chief Executive toward wealth and progress. To become wealthy and progressive, the local leaders are united to implement relevant programs, projects, and activities for sustainable agriculture and tourism development.
Alegria envisioned as the organic farming capital of Surigao del Norte and premier tourism destination of Caraga region with God-centered and resilient people living in a diverse and life giving eco-system, climate adaptive infrastructure support facilities governed by pro-active and responsible leaders. To fulfil this vision, local leaders of Alegria encourage local farmers and investors to participate and invest in organic farming technology. The current administration advocates not only for the tourist destinations promotion of the locality but also support and sponsor for eco-tourism and agri-tourism advancement.