Through numerous donations and bequests to various museums and institutions of higher education, Marquessa Arconati Visconti, born Marie Peyrat (1840-1923), contributed significantly to the enrichment of public collections and to the development of the teaching of history and art history, both in Paris and beyond, particularly in Lyon, Toulouse, and Angers. Deeply repub­lican, a Dreyfus supporter, and anti-clerical, she entertained friendly relations with a number of Protestants who may have influenced her liberalism in the literary domain as well as the arts. Those who belonged to this world of erudition included Gabriel Monod (1844-1912), Auguste Molinier (1851-1904) and his brother Émile Molinier (1857-1906), as well as Alfred Morel-Fatio (1850-1924), alumni of the École normale supérieure and the École des chartes, directors of studies at the École pratique des hautes études, professors of the École des chartes and the École du Louvre, and chair holders at the Collège de France. Raoul Duseigneur (1844-1916), collector and antique dealer, in whose memory the marquessa multiplied her donations upon his death in 1916, her “faithful friend”, no doubt was the marquessa’s companion, sharing in particular her taste for art object collections