Marcelo Hilario del Pilar y Gatmaitan: (August 30, 1850—July 4, 1896) was a celebrated figure in the Philippine Revolution and a leading propagandist for reforms in the Philippines. Popularly known as Plaridel, he was the editor and co-publisher of La Solidaridad. He tried to marshal the nationalist sentiment of the Filipino ilustrados, or bourgeoisie, against Spanish imperialism.

Marcelo H. del Pilar was born in Cupang (now Barangay San Nicolas), Bulacan, Bulacan, on August
30, 1850, to cultured parents Julián Hilario del Pilar and Blasa Gatmaitan. He studied at the Colegio de San Juan de Letran and later at the University of Santo Tomas, where he obtained his law degree in 1880.

Fired by a sense of justice against the abuses of the clergy, del Pilar attacked bigotry and hypocrisy and defended in court the impoverished victims of racial discrimination. He preached the gospel of work, selfrespect, and human dignity. His mastery of Tagalog, his native language, enabled him to arouse the consciousness of the masses to the need for unity and sustained resistance against the Spanish tyrants. In 1882, del Pilar founded the newspaper Diariong Tagalog to propagate democratic liberal ideas among the farmers and peasants. In 1888, he defended José Rizal's polemical writings by issuing a pamphlet against a priest's attack, exhibiting his deadly wit and savage ridicule of clerical follies.

In 1888, fleeing from clerical persecution, del Pilar went to Spain, leaving his family behind. In December 1889, he succeeded Graciano López Jaena as editor of the Filipino reformist periodical La Solidaridad in Madrid. He promoted the objectives of the paper by contacting liberal Spaniards who would side with the Filipino cause. Under del Pilar, the aims of the newspaper were expanded to include removal of the friars and the secularization of the parishes; active Filipino participation in the affairs of the government; freedom of speech, of the press, and of assembly; wider social and political freedoms; equality before the law; assimilation; and representation in the Spanish Cortes, or Parliament.

Del Pilar's difficulties increased when the money to support the paper was exhausted and there still appeared no sign of any immediate response from the Spanish ruling class. Before he died of tuberculosis caused by hunger and enormous privation, del Pilar rejected the assimilationist stand and began planning an armed revolt. He vigorously affirmed this conviction: "Insurrection is the last remedy, especially when the people have acquired the belief that peaceful means to secure the remedies for evils prove futile." This idea inspired Andres Bonifacio's Katipunan, a secret revolutionary organization.

Del Pilar's militant and progressive outlook derived from the classic Enlightenment tradition of the French philosophies and the scientific empiricism of the European bourgeoisie. Part of this outlook was transmitted by Freemasonry, to which
Del Pilar subscribed. "Plaridel’s writings in Tagalog were forceful. Rizal’s writings in Spanish were not understood by most Filipinos."

Plaridel was the pen name of Marcelo H. del Pilar, one of the great figures of the Philippine Propaganda Movement, the heroic group whose writings inspired the Philippine Revolution. He wrote "Dasalan at Tuksuhan" and also made a parody of "Our Father", where the "father" was the friar who in a way, abused the Filipinos back then.

Plaridel is the chosen "patron saint" of today’s journalists, as his life and works prized freedom of thought and opinion most highly, loving independence above any material gain.[who?] He died of tuberculosis in abject poverty in Spain,
1896.