Stoenescu had contact with the painting at 15 yo, when the French painter Leopold Durangel (1828-1898) comes into his parents' house to do a portrait of his mother. After visiting the retrospective exhibition Nicolae Grigorescu, opened in 1897 in Bucharest at the Romanian Athenaeum, he decided irreversibly to follow the same path.
He studied at the Julian Academy and at the National School of Fine Arts in Paris with Jean-Paul Laurens, with whom he collaborated in the execution of the tapestry cartoons and some wall decorations. If the beginning of his career was influenced by Grigorescu, Stoenescu gradually broke away from any influence, building a highly personalized style.
Stoenescu painted genre scenes, landscapes, still life, notably through subtle gray tones, but was mainly a virtuous portraitist, by the gift of an exceptionally laconic expression and distant vision, solemn, but not without expressiveness. Stoenescu´s portraits compel recognition, in terms of consummate execution, offhanded touch and spontaneous inspiration. Attentive to psychological details, the painter proved capable to transcribe reality faithfully, to select the essential and subordinate coloristic effects to expressiveness.
Painted in a wide range of styles, with an extraordinary verve, his portraits illustrate the talent of a gifted artist, to capture, with no hesitation, and to define clearly the universe of a human face as well as to concentrate, into a single image, the history of a lifetime. In Romania, as well as abroad, he was acknowledged as the artist who made the portraits of different officials, state leaders, members of the aristocracy, of wealthy intellectuals, of fashionable, distinguished ladies. He made them quickly, without endless sessions. He was a virtuoso, a magician of the brush.
Endowed with exceptional qualities and moreover having received a remarkable education, Eustaţiu Stoenescu created an oeuvre, which focused attention on him on three continents: Europe, North America an Asia. Thus, his participation in the great exhibitions of the time or his one-man shows in Paris, Venice, New York, London, Rome, Geneva, Bucharest etc. brought him the unanimous appreciation of experts, critics, the press and the art collectors. Numerous prizes, special honors as well as the purchase of his paintings for great museums and private collections from France, Italy, the USA, Great Britain, Belgium, and Holland etc. established him internationally.
As a constant presence in the fashionable circles of the time, Stoenescu had the image of a cosmopolitan character, refined and somewhat arrogant. Painter of great talent, considered one of the greatest portrait painters of the time, Eustaţiu Stoenescu entered into obscurity after the WWII, after his death being almost forgotten.