De Quirós was a restless student, and often skipped classes to spend time among the area's gauchos; during one such opportunity, he witnessed a duel and, inspired by the event, created his first known painting.
He then relocated to Mallorca, the largest of the scenic Balearic Islands of Spain, and lived there until 1910, making brief visits to Rome for the 1905 World's Fair, to the Venice Biennale, and to Buenos Aires, where he exhibited on Florida Street alongside Pío Collivadino and Fernando Fader.
María Antonelli, an unhappily married 18-year-old resident of Florence, met de Quirós during this interim, running away with him and eventually bearing him two children.
The 1914 death of his estranged father, as well as the outbreak of World War I, prompted de Quirós to relocate to the family home in Gualeguay.
Thirty works from his series "the gauchos" were acquired by National Fine Arts Museum in 1965, and his native province awarded him with their Legion of Merit in 1967.