[4] Aware of his natural artistic talent, his family sent him to Paris when he was 18 to study with the painter and sculptor Auguste Debay.
He was among the academic painters who satisfied a social demand for aggrandising, even propagandistic historical works in the early years of the Third Republic, after the defeat in the Franco-Prussian War.
Sometimes called 'the painter of the Gauls',[11] he also depicted other scenes of early medieval history, often clashes between different peoples, such as campaign-hardened Romans in breastplates reinforced with metal battling daring Celts who are bare-chested, with only helmet and shield for protection.
[12] More unusually among historical artists of the time, he also depicted the Franks, whose contribution to French history was then generally underrated in favour of the Gauls.
[16] Pepin the Short's overthrow of Childeric III with the agreement of Pope Zachary and the deposed king's imprisonment in the Monastery of St. Bertin at Saint-Omer is the subject of his painting The Last of the Merovingians, for which he reportedly used one Jean Marie Dagobert as his model.
[8] Having met Théodore Hersart de La Villemarqué, who had published a collection of popular Breton songs, Barzaz Breiz, around 1884 he based on one of the songs his Flight of King Gradlon, depicting the king fleeing on horseback from his city of Ys as it is swallowed by the sea; St. Winwaloe urges him to jettison his only child, Dahut.
[22] In 1880 he painted what, according to Bonnie Effros, was his most famous Merovingian painting,[8] The Sons of Clovis II, also called Les Énervés de Jumièges (the enervated men of Jumièges), based on a legend concerning the 7th-century Merovingian king Clovis II: after rebelling against their father, the two princes are said to have been punished according to their own mother's suggestion by the removal of their vital force ("enervation") through the destruction of the tendons of their muscles; they were then set adrift on a raft in the River Seine, at the mercy of God, but according to the legend they were rescued by the monks of the Abbey of Jumièges[23] and later reconciled with their parents.
The painting evokes varying and strong reactions; Simone de Beauvoir wrote in 1960 of "calm horror".
The second version, with greater emphasis on the grandeur of nature, was kept by Luminais; after his death it was acquired by the State and in 1912 was deposited in the Musée des Beaux-Arts in Rouen.
[23][25] At his summer studio in Douadic, he painted works reflecting his love of nature and of hunting, such as: Luminais was one of five artists who collaborated between 1886 and 1889 on a monumental fresco, more than 1,500 square metres (16,000 sq ft) in area, for the interior of the dome of the Paris Commercial Bourse, representing the history of intercontinental trade.