Louis is usually credited with the best-known of their paintings, a series of scenes depicting peasant life; he may have visited Italy, and been influenced by the Dutch artist Pieter van Laer, who was based in Rome but also passed through France in the mid-1620s.

Their choice of subject was unusual for the time: the world of Paris was busy with mythological allegories, and the "heroic deeds" of the king, while the three Le Nain devoted themselves chiefly to these subjects of humble life such as Peasant Meal (1642), Boys Playing Cards, or A Farrier in His Forge, three pictures now in the Louvre.

Their Adoration of the Shepherds in London (National Gallery) is an exception, and many other civic and church works may have been lost in the French Revolution.

[4] The Le Nain paintings had a revival in the 1840s and, thanks to the exertions of Champfleury, made their appearance on the walls of the Louvre in 1848.

Champfleury was a friend of the Realist painter Gustave Courbet, and a theorist of Realism and writer on French popular arts.

The "naive" quality of these works, with their static poses, "awkward" compositions and peasant subjects were admired and may well have exercised some influence on many nineteenth-century artists, notably Courbet himself.