His boyhood was spent in Arévalo in the province of Ávila, where he was born March 11, 1821. The village priest taught him Latin, and later he may have been a student at the University of Valladolid. Of the years that passed before he came to Madrid we know little besides a few anecdotes. According to one of these Sanz paid youthful court to the daughter of a glazier whose ruin was threatened by lack of business. The daughter told young Florentino of her father's difficulties in the course of an evening interview, whereupon the ambitious lover quickly organized a band of followers and broke all the windows in Arévalo.
Early in February of 1843 he was in Madrid, where he began to write for the newspapers. Two years later a few poems published in the Semanario Pintoresco, El Heraldo, and La Risa won him some recognition. He now identified himself with the group of romantic poets who held their meetings in the famous Café del Príncipe. His sonnet "La Discordia," published in the Semanario Pintoresco, February, 1843, furnishes indisputable evidence of his romantic tendencies. In it a waning moon, fratricide, corpses, "infernal sonrisa," and an agonized mother provide all the thrills of romantic horror; but it may be wiser to pass over in silence such outbursts as this.
As a member of a circle which gathered in the Café del Recreo (1846) he lived in the very thick of romanticism. Its meetings are thus described:
At that time there existed in Madrid a club of literary fledglings. The majority of the young men who ten years later had won conspicuous places in the world of letters gathered there without knowing exactly why. The nucleus at the Café del Recreo had been formed by no one, nobody was formally presented, no one of our number had been a friend or schoolmate of any one of the others; the gathering was there because it was there, it existed because it existed. The company included besides Sanz himself the poets Mariano Cazurro, Antonio Trueba, Ventura Ruiz Aguilera, Antonio Hurtado, José Albuerne, Antonio Arnao, the journalist Eduardo Asquerino, the statesman Cánovas, and the dramatist Fernández y González.—José de Castro y Serrano, Prólogo (pp. ix-x) to "Obras de Francisco Zea," Madrid, 1858.
The movements and activities of Sanz in the literary world began to be chronicled in such papers as the Fandango, published by Wencelao Ayguals de Izco and Francisco Villegas. They speak of him as "our friend and collaborator." From them we learn that he was occupied in writing semblanzas, or portraits, of the most conspicuous literary lights of the hour. Though these semblanzas seem to have circulated in manuscript, they never were printed. Eduardo de Lustoñó declared[1] that Sanz was always a presumptuous person and particularly so in 1845. Lustoñó wrote a squib, stupid enough to be sure, in which he implies that the purpose of the semblanzas was to ridicule the pedants. Lustoñó enrolled him as private soldier in what he called his "Regiment of Men of Letters," but it was an unconscious tribute to the ability of Sanz to admit him even as a private in a regiment whose officers were: Colonel, Quintana; Majors, Hartzenbusch, Tassara; Captains, Bretón, Rivas; Lieutenants, Campoamor, Mesonero Romanos, and Frías,—all of whom have won enduring fame.
On the night of February 1, 1848, "Don Francisco de Quevedo" was presented in the Teatro del Príncipe. The distinguished actor and poet Don Julian Romea chose the occasion for a benefit performance. The play was an instant success. The number of the Semanario Pintoresco which followed the first performance printed a flattering review:
The drama "Don Francisco de Quevedo," presented at the Príncipe for the benefit of Don Julian Romea, has won for its author, Don Eulogio Florentino Sanz, a place of distinction among our dramatists. Success in portraying the personage from whom the piece takes its name, resourceful stagecraft, daring situations, and a versification now serious, now gay, frolicsome or sorrowful, but always agreeable, facile, and correct, these are the distinguishing features of the play with which Señor Sanz has made himself known to the theater-going public. Don Julian Romea gave an able interpretation of the part of Don Francisco de Quevedo, Señora Díaz was excellent as the Infanta Margarita. The rest of the cast contributed ably to the success of the drama.
This notice conveys some idea of the striking enthusiasm with which the piece was received.
In keeping with his literary predilections Sanz had already identified himself politically with the progressive liberal party.
In the years immediately preceding the overthrow of the Conservatives (1845) Sanz gave his services to the progressive liberal cause. In 1849 he was editor of La Patria, whose first number appeared on January 2. It announced a policy of political moderation, but its real purpose was the most strenuous opposition to the government of the reactionary conservatives. Sanz was generally believed to be editor-in-chief. Suddenly on the fourth of January he resigned[2] with no explanation whatsoever to the subscribers. A little later he appeared on the staff of La Víbora, periódico venenoso redactado por los peores literatos de España, bajo la dirección de nadie ("The Viper, a venomous paper, edited by the worst scribblers in Spain, under the management of nobody"). The censorship was as crushing as in the days of Larra. Later, in September, La Patria announced another periodical, La Sátira, adding that it was to be under the direction of the editors of the short-lived Víbora. This second attempt also met with disaster. Again in June of 1851 Sanz resigned from another paper, El Mundo Nuevo.