Isabelo de los Reyes y Florentino, also known as Don Belong (July 7, 1864 – October 10, 1938), was a prominent Filipino patriot, politician, writer, journalist, and labor activist in the 19th and 20th centuries.

[3]: 256 Elías and his children shunned Leona away from the family due to her progressive feminist and pro-equality ideals, which were viewed negatively under the Spanish colonial patriarchy.

[5] This left Isabelo without a mother as Elías entrusted his six-year-old son to the care of Don Marcelino Crisólogo, a wealthy relative[8] who was also a writer in the vernacular.

[1] Beluco, as he was called in his youth, was enrolled in a grammar school attached to the local seminary run by Augustinians (Seminario de Vigan); their harsh discipline made him a lifelong critic of friars.

Her progressive ideals and feminist literary works were given recognition a decade later internationally, and a century later in her home country where a statue was built in her honor in Vigan's main street of Calle Crisologo.

De los Reyes wrote Folk-Lore not just as a book for legends and fables, but eventually as "a general archive at the service of all sciences", expanding his definition of "folklore" to include "popular knowledge relevant to all sciences", including sections on religion, customs, literature, and articles on Diego Silang, millenarian revolts, and local miracles of the Virgin Mary.

[11] De los Reyes declared that he founded El Ilocano to "serve [our] beloved pueblo Ilocos by contributing to the enlightenment of her children, defending her interests."

De los Reyes, however, sold types to Emilio Jacinto for the Katipunan's printing press, and he later claimed that he made a financial contribution to the Liga.

[3]: 265–266  De los Reyes was deported aboard the SS Alicante in June 1897, and was interred at the Montjuïc Castle in Barcelona for six months, before being released as part of the terms of the Pact of Biak-na-Bato.

[8] In this capacity, de los Reyes helped rally Filipino support against the Americans, thinking that this would create conditions favorable to the Philippines.

He had received assurances from the governor-general Basilio Augustín regarding autonomy, and together with other Filipinos in Spain, offered to return to the Philippines to organize militias to fight the Americans.

Given guarantees by the American consul in Barcelona that he will not be harassed upon his arrival in the Philippines, he left Spain on September 14 aboard the steamer Montevideo.

On October 25, 1901, ten days after he returned to Manila, he sought authority from the Philippine Commission to publish his Defensor de Filipinas, which was refused.

On October 31, he appeared before the commission, with Pedro Paterno and Pascual H. Poblete to seek permission to form a political party, the Partido Nacionalista, which was also denied.

In 1901 to 1902, Hermenegildo Cruz and other members of the Carmelo and Bauermann publishing house approached de los Reyes to seek advice in forming a cooperative store for rice and other staples.

[3]: 278  The UOD was the first labor union federation in the Philippines, soon being joined by neighborhood associations from Cavite, Quiapo, Santa Cruz and Sampaloc; company guilds from the San Miguel Brewery and L.R.

[12]: 14 As conceived by de los Reyes, the UOD's aim was to "achieve the longed-for alliance between capital and labor" by bringing together workers and employers in a spirit of friendship, mutual respect, and recognized interdependence.

He had observed that workers in Europe had clubs and cafes where they could read newspapers and discuss current events, and wished to emulate that in the Philippines.

[3]: 279  De los Reyes was eventually released on January 30, 1903, by Governor William Howard Taft, stating that the statute "was not in line with current American thinking on the subject" and was given the condition that he would henceforth shy away from labor organizations.

He also sought to continue his translation of the bible and to oversee its printing in Yokohama, although others suggest that his true purpose was to meet with Filipino revolutionary general Artemio Ricarte, who was in exile at the time.

[8] Details are unclear whether de los Reyes met with Ricarte in Yokohama[11] or in Hong Kong,[3]: 284  although it was certain that a meeting took place between the two in Manila.

As board member, he worked on social welfare ordinances, pushed for "Filipinization" of the civil service, and filed resolutions urging immediate and absolute independence of the Philippines.

A frail de los Reyes' last foray into politics was when he ran in the 1935 Philippine legislative elections, losing badly.

De los Reyes executed a document of retraction from his Aglipayan faith on September 14, 1936, two years before his death, as attested by some of his Roman Catholic daughters, although the authenticity of the so-called metanoia was vehemently contested by other family members asserting that de los Reyes no longer had full control of his faculties that time due to deteriorating health and old age.

However, after the World War II, his remains were permanently transferred to the María Clara Parish Church of the Iglesia Filipina Independiente in Sta.

In this capacity, he wrote multiple devotional and doctrinal texts such as the Biblia Filipina, Oficio Divino, Catequesis, Plegarias, Genesis Cientifico y Moderno and the Calendario Aglipayano.

[11] In late December 1898, he married María Ángeles López Montero (the daughter of a retired Spanish infantry colonel) in Madrid, also in a Roman Catholic ceremony.

With his own family spanning Roman Catholic and Aglipayan traditions, de los Reyes was tolerant of religious diversity among his children.

His namesake Isabelo de los Reyes Jr. (1900–1971), a son from his second marriage with Lopez and whom he shares the same death day with at October 10, although baptized Roman Catholic, was ordained an Aglipayan priest and later became Obispo Máximo IV of the Church for 25 years.

Throughout his life, Isabelo de los Reyes wrote and published multiple works in various subjects, such as history, folklore, politics, and religion.