Born in a small village near the Sarthe, Lebasque enrolled as a student at his local art school, the Ecole des Beaux-Arts, in Angers. In 1886, he went to Paris and briefly studied under Bonnat. He later studied under Humbert and aided in his decorations of the Panthéon. His made his début at the Salon des Indépendants in 1896 and he also participated in the Salon des Artistes Français. In his youth he frequently visited the ageing Pissarro, who lived near Paris, and in his studio he learned the crucial lessons about line, form and colour. Undoubtedly the influence of Pissarro upon Lebasque was far greater than that of Bonnat. As the era of the first great impressionists moved towards its close with Pissarro’s death in 1903, another era in French art began, with Lebasque participating in the inaugural exhibition at the Salon d’Automne, on whose committee he gave lifelong service. He was at one time wrongly classified with the Fauves, this doubtless as a result of his exhibiting alongside them in the Salon d’Automne during the exciting and innovative first few years of the 20th century. At the Salon des Indépendants in 1893 he met Luce and Signac for the first time and under their influence adopted the pointilliste technique. Lebasque settled with his family in Lagny to the east of Paris until 1906, mostly painting scenes along the wooded banks of the Marne. At about that time, he was introduced to the Midi by his friend Albert Manguin and the region wrought a dramatic transformation on his painting, from which he never turned back. He also spent much time painting in other far-flung regions of the land, in Vendée, Brittany, Normandy, Sanary (near Toulon) and Nice. For periods in 1912, 1915 and 1921 he lived in Les Andelys, on the Seine to the west of Paris and used the backdrop of steep chalky cliffs against the leafy river to great effect in his paintings.
For more than thirty years he used members of his own family as models in his paintings and the artefacts, interiors, houses, gardens, riverbanks and beaches in his pictures were drawn from places where he stayed for long periods. After spending a few seasons in Saint-Tropez and Saint-Maxime, he finally decided on Le Cannet, and made his permanent home there in 1924. He evolved a style all his own, however, creating a distinctly pleasing, understandable, and accessible way of painting. His subjects for the most part are landscapes, flowers, still-lifes, nudes and figures, always characterised by an attractive use of light and colour. During Lebasque’s lifetime his work was widely admired by the public and was well received by the all-powerful critics of the time, whose opinions carried great weight. Lebasque worked on a few public projects, most notably the décor of the Théâtre des Champs-Elysées.