He was the son of metalworker and damascener Plácido Zuloaga and grandson of the organizer and director of the royal armoury (Don Eusebio) in Madrid.

He was nearly destitute, and lived off some meager contributions by his mother and the benevolence of fellow Spaniards, including Paco Durrio, Pablo Uranga, and Santiago Rusiñol.

Continuing his studies in Paris, where he lived for five years, he was in contact with post-impressionists such as Ramon Casas, Gauguin and Toulouse-Lautrec,[7] yet his tendencies were always to a thematic that was more ethnic in scope.

He attempted to gain success during a sojourn in London; but lackluster patronage led him to return to Spain, settling in Seville, then Segovia, and developed a style based on a realist Spanish tradition, recalling Velázquez and Murillo in their earthy colouring and genre themes.

[8] He favored earth or muted tones, including maroon, black, and grey, with the exception of colorful folk attire or the bright red cassock in some paintings.

Zuloaga and his patrons felt slighted in 1900, when his painting Before the Bull-fight was rejected for inclusion into the Spanish representation at the Universal Exposition in Brussels.

Brinton in his review of an exposition in America in 1909, he states that: It is this racy and picturesque life which Zuloaga seeks above all else to place on record, and it is these popular types unspoiled by ruthless modernism which he pursues into the farthest corners of his native land.

He will haunt for hours a fiesta on the outskirts of some provincial town, or hasten away to the mountains, passing months at a time with smugglers and muleteers, with the superstitious fanatics of Anso in the extreme north of Aragon or with the monkish cutthroats of Las Baluecas, a little village on the southern boundary line of Salamanca.

Stylistically, the directness of the Siege painting also avoids modernity's challenge to realistic depictions: Fascism was not endeared to complex symbolism such as found in works such as Guernica.

Brinton in his 1909 essay was prescient of Zuloaga's future enamourment with Falangism: He personifies in extreme form the spirit of autocracy in art, the principle of absolutism so typical of his race and country.