1850 July 30 Léon Emile Aldala Delachaux is born near Villers-le-Lac (Doubs, France).
His mother, Mélanie Henry, is French and Catholic.
His father, Louis-Auguste Delachaux, is Swiss and Protestant.

1851 August 9 His parents, both clockmakers, get married.

1850-1855 Childhood in Switzerland, at Planchettes in the canton of Neuchâtel, then at Morat in the canton of Fribourg. Louis and Mélanie have four girls, none of them survive.

1855 Destitute, his father commits suicide by jumping into the Doubs.

1859 His mother, now a widow, takes him to Cairo.

1868 Léon departs Cairo on his own for Marseille, probably due to a disagreement with his stepfather, Albert Kollinsky. Works as a carriage painter, then moves back to his family’s clock-making roots in Switzerland, where he finds work as an engraver of precious metals.

1872 According to family sources, a representative from the American jewelry company, Tiffany, offers the talented Léon an opportunity to work as an engraver in the United States. He boards the ocean liner Ville de Paris to cross the Atlantic for New York.

1875 April 29 Philadelphia: Léon marries Marie-Appoline Noël (Pauline). Her family is originally from Etival (Vosges, France). They emigrated to the US in 1853.

1875 December 14 Birth of their son Clarence.
Léon is now recorded as a watchcase engraver.

1876 Opening of the Centennial International Exhibition in Philadelphia. Léon discovers the works of art and paintings exhibited in the Memorial Hall.

1876-1881 Takes academic art classes at the Pennsylvania Academy of the Fine Arts (P.A.F.A.), and then studies under Thomas Eakins (1844-1916), father of American Realism, professor of painting and drawing at the P.A.F.A. from 1879 to 1886.

1878-1880 His friend Carol Storck (1854-1926), the Romanian sculptor who also studied at P.A.F.A., joins him at 1934 Locust Street in Philadelphia.

1879-1916 Exhibits in the United States: Philadelphia, Pittsburgh, Louisville, Boston, New York, Chicago, San Francisco. He also participates in exhibitions in South America.

1882 Expresses a desire to return to France. An agreement with his picture dealer enables him to finance his voyage; in exchange, he sends his French pictures to Philadelphia.

1883 Obtains US citizenship for fiscal reasons.
With his wife and son, he arrives in France and settles at Levallois-Perret. For several years, he continues to send his works to the United States. He exhibits in the US until 1916.

1883-1884 Meets the painter Pascal Dagnan-Bouveret (1852-1929), who, along with Thomas Eakins, was a student of Jean-Léon Gérôme (1824-1904).

1884 The family settles at Grez-sur-Loing, an international art colony near Fontainebleau and Barbizon.

1884-1890 Exhibits at the Salon de la Société des Artistes Français.

1887 Receives an honorable mention at the Paris Salon for his picture Crux Ave à Pâques (Kunsthaus, Zurich, Switzerland).

1888 Léon Delachaux and his family settle in Paris, 20 rue Durantin in Montmartre.

1889 Paris Exposition Universelle (World’s Fair).
Receives a bronze medal for his picture La Louée à Château-Landon (Musée des Beaux-Arts, La Chaux-de-Fonds, Switzerland).

1889-1900 Travels to central France – Puy de Dôme, Indre, Creuse, Cher, where he paints rural life. Suffering from poor health, and subject to angina attacks, he takes a therapeutic cure in Auvergne. On the way, a sudden attack forces him to stop in Saint-Amand-Montrond where he is treated.

1891-1914 Exhibits at the Salon de la Société Nationale des Beaux-Arts, of which he becomes an Associate in 1895, a Full Member in 1901, and a Member of the Review Panel in 1903, 1904 and 1909.

1898 October 10 Exhibits at the Galerie Georges Petit along with Paul Vogler, Théophile Steinlen, Antoine Bourdelle, Frank Brangwyn, Emile Claus and Harry Van der Weyden.

1900-1919 Moves into a house with an art studio in Saint-Amand-Montrond (Cher, France).

1902 His son, Clarence, creates the Delachaux company.

1903 Exhibits at the Galerie Silberberg, rue Taitbout in Paris, with his friend François Guiguet and the painter Gaston Hochard.

1907 Recovers his French nationality.

1909 September 5 Death of his mother, Mélanie Kollinsky, in Nice (France).

1911 May 30 Clarence marries Marie-Louise Lefebvre in Paris.

1911 November 4 Receives the Legion of Honor.

1913 August 14 Clarence acquires his first property at Grez-sur-Loing.

1919 January 27 Death of Léon Delachaux in Saint-Amand-Montrond. In his last will and testament, he expresses his wish to be buried without ceremony at Grez-sur-Loing, where Clarence and his family reside.

1922 November 10 Death of Marie-Apolline in Paris. She is buried next to Léon, in Grez-sur-Loing.

1938 According to his father’s last wishes, Clarence donates twelve oils on canvas and several drawings to the future Musée Saint-Vic de Saint-Amand-Montrond to form the core of a collection.