Nicasio Idar, newspaper editor and publisher and civil-rights advocate, was born in Point Isabel, Texas, in 1855, either on December 11 or 14, the son of Manuel and Eleuteria Espinoza Idar. He moved to Laredo in 1880 after attending school in Corpus Christi. He and his wife, Jovita, had eight children, of whom three, Jovita, Clemente, and Eduardo Idar, were involved in the publication of Idar's La Crónica in Laredo. Idar's seventeen-year publishing career also included La Revista, a Masonic newspaper with an international distribution. He was active in nearly all local social and fraternal Texas Mexican organizations in Laredo and helped found the Caballeros de Honor and the Sociedad Hijos de Juárez. He also served as a justice of the peace and assistant city marshall in Laredo.
La Crónica probably began publication in the 1890s, though Idar perhaps did not assume the role as publisher and editor until 1910. Under his leadership the paper took on major political, social, economic, and educational issues facing Mexican Texans in the early 1900s. The newspaper's logo reflected this commitment: "We work for the progress and the industrial, moral and intellectual development of the Mexican inhabitants of Texas." La Crónica documented the segregation, lynchings, and denial of civil rights of Texas Mexicans. In a series of articles that ran during late 1910 and early 1911 under the rubric "The Mexican Children of Texas," Idar spoke out against separate schools and neighborhoods for Mexican Americans, who by linguistic segregation were "isolated and kept ignorant." He also reported social and working conditions of Mexican Texans in the interior of the state. Often La Crónica pointed out that most Mexican Texans labored in menial jobs in agriculture or domestic work and that the few professionals among them lived along the border. The paper covered incidents of injustice, including the "barbarism" in the case of Antonio Rodríguez, who, after being accused of killing an Anglo woman near Rocksprings, was burned and hanged by a mob. Idar sought also to make La Crónica a mouthpiece for the organizations in which he was involved and for news on the cultural life of Laredo. The newspaper often reported on theater groups from Mexico and other artistic ventures. Like other Spanish-language newspapers La Crónica was a literary vehicle for poets and is an important record of Texas Mexican literature of the early twentieth century.
Idar organized the Gran Concilio de la Orden Caballeros de Honor not long after 1910. The council was meant to unite Mexican Texans for cultural and intellectual discussions and to gain the respect of the "americanos." The group called for members that were noble, generous, and patriotic persons who would also provide assistance and fraternity to other Mexican Texans. Idar and his family organized a conference in Laredo to address racial discrimination on September 14–22, 1911. The Congreso Mexicanista focused on the need for teaching Spanish in schools, women's groups, and protection of the lives and land rights of Mexican Texans. Through La Crónica the Idars urged Caballeros de Honor lodges and other Mexican-Texan groups to send delegates to the convention. They tried, evidently without success, to establish a group called La Gran Liga Mexicanista; its intended motto, "por la raza y para la raza," foreshadowed the Raza Unida party.
Idar continued to publish his newspaper until he fell ill with an intestinal disorder. He died in his family home in Laredo on April 7, 1914. At his funeral, which was attended by many townspeople and members of social fraternities, he was eulogized as "a good father, noble friend, and benevolent counselor."