The history of this chair is sketchy but from what I have managed to cobble together from the internet I would offer the following.
This type of chair known as Carré Sunburst, French button, Pinwheel or just Spring Steel Chair appears to have originated in Paris, France, made by Felix Carré sometime in the1850s. In 1865 his chairs were described in a guidebook as "a real revolution". In 1866 he is said to have filed a patent in America, (later bought by Lalance and Grosjean) and possibly elsewhere. In 1870 an advertisement (shown below) was printed for Usine Carré displaying a variety of goods from chairs to velocipedes to greenhouses. It was in this year that the factory was badly damaged and sold on to another metal manufacturer. Whether Carré carried on elsewhere or just gave up his patent I don't know, but these spring steel chairs continued to be made by others in Europe and America including Val de Osne, Schlesinger Wiessener & Co of Vienna and New York. In 1890 the factory was sold again to Wessbecher, another garden furniture manufacturer who were known to be still advertising their furniture in 1959.
The Achilles heel of this type of chair is the interface between the Wrought Iron or Mild Steel outer ring and the spring steel slat that provides the springy support.
If left out in the rain for long periods, the rain will sit in this crevice and begin the rusting process. Once spring steel starts to rust it proceeds at quite a pace leading to a snapping of the seat slat at this juncture. In the days of "white lead" paints the onset was slower but now that we no longer have access to these paints, regular observation and maintenance is vital from day one.
Personally, I would prefer to keep them indoors all the time or at least brought indoors every night and never used out doors in Rain and Snow.