Guido Borgianni was born in New York. His Florentine father, Roberto Borgianni, was a leather merchant and his mother, Sara Herreshoff, was born to one of the wealthiest families in the United States. Guido was less than a year old when his parents' marriage ended, and his father brought him back to live in Florence.

There he would develop extraordinary talents as a draftsman and painter. He attended the Academy of Fine Arts in Florence. In the early days of his career, he signed his works in black. His signature would later change to red, when he became a “divisionist”.

Divisionism was an artistic phenomenon born at the end of the 19th century, derived from Neo-Impressionism and characterized by the separation of colors into single points or lines that interact with each other in an optical sense.

Among his admirers were Oskar Kokoschka a well-known Austrian painter and playwright. Other notable fans included neo-realist director and actor, Vittorio De Sica.

In 1946, Borgianni exhibited his paintings at the Rome Quadrennial (an Italian National Institution promoting Italian contemporary art).

Over the years, the artist received many awards recognizing his work including:

the Mostra Nazionale del Fiorino in Florence (1950);
the Academician of the Accademia delle Arti del Disegno award in Florence (1954);
and the First Prize at the Mostra del Ritratto alla Casa di Dante in Florence (1957)

His works are housed in the Gallery of Modern Art of the Palazzo Pitti and the Uffizi, Florence, and are also part of various collections around the world: the Gallery of Modern Art of Bologna, the Kunsthalle of Bielefeld (Germany), as well as part of many private Italian and foreign collections.