The first of the Butterfly chairs came out of the Argentinian architectural firm, Grupo Austral, in 1938. The Austral Group was comprised of Jorge Ferrari-Hardoy, Juan Kurchan and Antonio Bonet, who had met as assistants in Le Corbusier's Paris atelier. The chair is occasionally known as the BKF chair, for Bonet-Kurchan-Ferrari, but an official letter from the firm attributed primary authorship of the design to Ferrari-Hardoy, which is why it is also occasionally known as the Hardoy chair.
The chair may have been designed for a project the Austral Group was building in Buenos Aires, but it was first introduced at the 3rd Salon de Artistas Decoradores, a design exhibition held in that city in 1940, where it won two prizes. It also attracted the attention of Edgar Kaufmann jr. [sic] (he didn't like the 'jr.' capitalized), who had just become the Curator of Industrial Design at the Museum of Modern Art in New York. Kaufmann bought two chairs, one for MoMA's collection, and one for his parents' new Frank Lloyd Wright-designed house, Fallingwater. Kaufmann considered it to fall within MoMA's concept of "Good Design," because it was functional, handsome, lightweight, and relatively inexpensive.
First mass-produced in the US by Alvar Aalto's company Artek (the name a contraction of "art" and "technology"), the chair was composed of two bent tubular steel rods welded together, over which a leather sling was hooked, creating a suspended seat. Knoll bought the US rights to the chair in 1947, but stopped production in 1951 because of a seminal court ruling that did not allow Knoll to sue other manufacturers for making unauthorized reproductions of the Butterfly chair — the court determined that Hardoy's chair was itself too similar to earlier precedents to claim copyright protection. While the Butterfly chair was perhaps the first of its kind in tubular steel, similar constructions in wood had been around at least since the 1850s, when an English engineer named Joseph Beverly Fenby created a folding "campaign" sling chair for use by the British military (image 5).
Because of the similarities within this type of chair, the ones you can buy today are almost certainly not the Hardoy, Artek or Knoll originals — you can often see differences in how the rods are welded together, and of course in the type of cover. Today, we see the Butterfly chair being used in upscale contemporary interiors (Images 1-4, 6 & 7), as design mavens rescue the style from its dorm room associations, reclaiming it on behalf of its prestigious origins.
Images: 1 A circle of Butterfly Chairs at the Parker Palm Springs; 2 Orange butterfly chair in an interior by Parsonson Architects, via Desire to Inspire; 3 Leather butterfly chairs in a Roman and Williams interior, via Desire to Inspire; 4 Photograph by Rachael Smith, via Remodelista; 5 The Tripolina chair, originally designed in the 1850s by Joseph Beverly Fenby for the British military, via Design Boom; 6 Photograph by Angus Fergusson for House and Home; 7 Butterfly chairs in a Lynn Morgan interior, via Elements of Style.