For museumgoers already familiar with the Rococo masterpieces of Jean-Antoine Watteau (1684-1721), a special exhibition at the Frick will illuminate a little-known aspect of his oeuvre. Filling a single gallery of the Frick’s lower level, Watteau’s Soldiers: Scenes of Military Life in Eighteenth-Century France, brings together four of seven surviving military paintings by Watteau, along with related drawings.

But for those not fully aware of Watteau’s achievements, this exhibit could further obscure an already misunderstood artist. The leading figure of French Rococo painting, Watteau is credited with inventing the fête galante genre—compositions of figures in finery engaged in outdoor festivities. His fête galante scenes inspired a generation of younger artists, including Pater, Lancret, Boucher and Fragonard.

Though Watteau died at 36, having spent most of his life under the reign of Louis XIV, his artistic legacy is tied to the school of painters he gave rise to, forever linking him to the pastel confections of his followers that flourished under Louis XV. (The Frick’s own Fragonard Room is an example of Late Rococo frivolity.)

For much of Watteau’s life, France was embroiled in the War of Spanish Succession (1701-1714), a long, bloody and costly conflict that consumed Europe. The painter’s hometown of Valenciennes, bordering the Spanish Netherlands, was close to some of the fiercest fighting. Though Watteau left for Paris in 1702 to pursue his career, war was on the painter’s mind during his early years in the capital.

Watteau’s biographer and friend, Edme-François Gersaint, noted that the young painter’s first-ever art sale was a canvas portraying “a departure of troops.” Exhibition organizer Aaron Wile believes that canvas may be “The Line of March,” ca. 1710, on loan here from the York Art Gallery. While soldiers ride toward the cannon fire on the horizon, Watteau captures interpersonal drama at the tail end of the cavalry charge, as a mounted officer appears to argue with an infantryman and his female companion.

Next to it, Mr. Wile installed “The Halt (Alte),” ca. 1710, an oil painting the curator thinks is the “likely pendant” to “The Line of March.” Gersaint recounts that Watteau’s first client was “so much pleased with the picture that he begged the artist to paint a companion piece.” Watteau, who used the money from the sale of his artwork to visit his hometown, sent his new collector “from Valenciennes a scene representing ‘A Halt of the Army’.” Borrowed here from Museo Thyssen-Bornemisza in Madrid, “The Halt” is an oval composition in which two leaning trees make a V in the center of the design, with resting soldiers all around.

Yet Watteau’s biography is sketchy, and there are reasons not to accept these two canvases as a pair. Mr. Wile concedes “there is no firm chronology for Watteau’s military works” and says he doesn’t have “a firm conviction about which paintings are actually being discussed” by Gersaint. Though scholars may disagree on the dates of the artworks here, these are all early works and comprise a fragment of Watteau’s output.

“The Portal of Valenciennes,” ca 1710-1711, the Frick’s picture of guards milling about, and “The Supply Train,” ca. 1715, are the only other paintings in this show. Like all Watteau’s military paintings, these pictures depict moments before or after the fighting, never the battle itself. Exhibited publicly for the first time, “The Supply Train” is on loan from a private collection. Set in a bivouac at twilight, soldiers in the foreground lay in the grass alongside seated women as a cauldron warms over a fire. Below a blue and pink colored sky, troops in the background set up camp for the night.

Visitors to this exhibition will obtain some insight into Watteau’s working method. Next to each of the four oil paintings here hang corresponding drawings. Unlike most of his contemporaries, who would plan their compositions out beforehand, Watteau’s paintings are improvised. In ‘La Vie D’Antoine Watteau,’ 1732, biographer Comte de Caylus writes, “Watteau never made a sketch, however slight, for any of his pictures. His habit was to draw all his studies in a bound sketch-book, so that he always had a great quantity ready for use … When the fancy struck him to paint a picture, he used to refer to his sketch-book, and having selected the figures which suited his purpose at the moment, would arrange them in groups, generally in reference to a landscape background which he already thought out or prepared.”

The drawings here support this account. Made with red chalk, these sketches from life demonstrate marvelous dexterity. Watteau conveys light and form with a few well-placed strokes of chalk. The soldiers on these pages are then transferred into landscapes, combined into compelling figure arrangements.

In Watteau’s time there was a big market for war paintings. Gentleman officers who had been to battle often collected paintings as mementos of their army days. Exhibit organizers have included a painting by 17th century Dutch artist Philips Wouwerman for context. Wouwerman’s military genre scenes were popular in France and probably familiar to Watteau.

The paintings gathered here might have been integral to Watteau’s artistic development. Perhaps these early experiments composing figures outdoors sparked the idea for fête galante scenes, with wounded soldiers swapped out for musicians and amorous couples. And perhaps his early exposure to the realities of war blessed him with a more sober outlook than his Rococo followers, helping him avoid the saccharine sensibility of his imitators. Nevertheless, these are not his best works. (For a true treasure by Watteau, museumgoers can go a few blocks north to see “Mezzatin,” ca. 1718-20, a crown jewel in the Metropolitan Museum of Art’s permanent collection.)

Biographer G. Dargenty wondered, “how, within the limits of so short a life, could this nervous, restless, sickly lad have produced a multitude of pictures, not one of which lacks some spark of genius, and many of which are masterpieces?” Though there are no masterpieces in this show, there are sparks of genius.

Watteau’s Soldiers: Scenes of Military Life in Eighteenth-Century France, on view through October 2, 2016 at The Frick Collection, 1 East 70th Street, 212-288-0700, www.frick.org

More information about Xico Greenwald’s work can be found at xicogreenwald.com