Largillierre's sumptuous three-quarter length portrait is characteristic of the artist's grandest works of the 1720s and 1730s: his sitter is opulently but informally dressed and assumes a rhetorical pose, the handling of paint is textured and velvety, the Rubensian palette is autumnal, russet and shimmering with light. Remarkable is the subject of the portrait: a beautiful young woman who gazes skyward -- perhaps contemplating of the stars -- and holds a pair of gold compasses in her right hand while resting her left hand on a celestial globe. Few portraits of women in the 18th century depict them in intellectual pursuits such as astronomy, mathematics, or any of the sciences that were ordinarily the province of highly educated men only.
These striking attributes support the traditional identification of the sitter as Gabrielle Emilie Le Tonnelier de Breteuil, Marquise de Châtelet (1706-1749), one of the great intellectual figures of the first half of the 18th century. Daughter of a Secretary in the court of Louis XIV, Gabrielle Emilie was married in 1725 to the Marquis Florént Claude du Chastellet, a military man and governor of Semur-en-Auxois in Burgundy. The now-standard spelling of her name -- Châtelet, rather than Chastellet -- was introduced by François Marie Arouet (1694-1778), known as Voltaire, who became her lover in 1733.
Under the tutelage of Maupertuis and Clairaut, the Marquise du Châtelet studied advanced mathematics in order to understand the quantifiable theories of the natural world expounded by Sir Isaac Newton. In 1737, she published a paper based on her research into the science of fire that predicted what is today known as infrared radiation, and in the last years of her life she completed the first French translation of Newton's Principia Mathematica. After her death in 1749, Voltaire had the manuscript published at his own expense: it helped make the Newtonian scientific method an integral part of the French Enlightenment and remains to this day the standard translation of Newton's work. Perhaps appropriately, a crater on the planet Venus is named in her honor.
The identification of this portrait is documented by the inscription, Mquise du Châtelet, par De Largilliere at the bottom of a smaller version of the Columbus portrait (present location unknown; sold, Paris, Galerie Georges Petit, Alfred Beurdeley Collection, 6-7 May 1920, lot 164). The presence of the globe is almost certainly meant to allude to Newton's theory of universal gravitation, and the marquise's fingers point to the spot on the globe at which appears the zodiacal sign of Scorpio - which Edgar Munhall (op.cit., 1976, p. 91) shrewdly noted was Voltaire's birth sign.
Judging from both the portrait's style and the sitter's apparent age, the painting should be datable to circa 1735-1740.