Boldini was born in Ferrara, the son of a painter of religious subjects, and in 1862 went to Florence for six years to study and pursue painting. He only infrequently attended classes at the Academy of Fine Arts, but in Florence, met other realist painters known as the Macchiaioli, who were Italian precursors to Impressionism. Their influence is seen in Boldini's landscapes which show his spontaneous response to nature, although it is for his portraits that he became best known.
Moving to London, Boldini attained success as a portraitist. He completed portraits of premier members of society including Lady Holland and the Duchess of Westminster. From 1872 he lived in Paris, where he became a friend of Edgar Degas. He became the most fashionable portrait painter in Paris in the late 19th century, with a dashing style of painting which shows some Macchiaioli influence and a brio reminiscent of the work of younger artists, such as John Singer Sargent and Paul Helleu. He was nominated commissioner of the Italian section of the Paris Exposition in 1889, and received the Légion d`honneur for this appointment.
In 1897 he had a solo exhibition in New York. He participated in the Venice Biennale in 1895, 1903, 1905, and 1912. He died in Paris on 11 July 1931.
, written in 2007 by the Italian composer Lorenzo Ferrero, which depicts the story of Donna Franca, a famous Sicilian aristocrat whose exceptional beauty inspired him and many other artists, musicians, poets and emperors during the Belle Èpoque.
A Boldini portrait of his former muse Marthe de Florian, a French actress, was discovered in a Paris flat in late 2010, hidden away from view on the premises that were unvisited for 70 years. The portrait has never been listed, exhibited or published and the flat belonged to de Florian's granddaughter who went to live in the South of France at the outbreak of the Second World War and never returned. A love-note and a biographical reference to the work painted in 1888, when the actress was 24, cemented its authenticity. A full-length portrait of the lady in the same clothing and accessories, but less provocative, hangs in the New Orleans Museum of Art.
The discovery of his painting in the 70-years-empty apartment forms the background to Michelle Gable's 2014 novel A Paris Apartment