The square is named after Aristide and Marguerite Boucicaut who in 1852 launched what may obviously be considered as the first real department store in the world. It kept the name “Le Bon Marché” - which could mean “cheapness”, or maybe rather should be interpreted as the “good bargain”? - from a previous shop founded in 1838 in which they had been associated for a few years. It was a great success and in 1869 the present large main building was launched, opening in the early 1870’s. The architect (Louis-Charles Boileau) asked for help by Gustave Eiffel for the structure of the building. (The escalators have of course been added later, designed by Andrée Putman.)
The success story continued. The employees were obviously well treated with a lot of social advantages, not so common those days. Other adjacent buildings were added. Today, this is probably the most luxury oriented department store in Paris. This is the place you rather would go if you want something of a certain standard. You find also a very nice bookshop and what I believe must be the food store with the largest assortment in Paris. I checked the olive oils; there were some 50 brands to choose from.Since 1984, Le Bon Marché belongs to the LMVH group (Bernard Arnault) and is definitely now a luxury department store, where you of course can buy what you “need” of the other brands of the group (Louis Vuitton, Loewe, Kenzo, Givenchy, Marc Jacobs, Dior Perfumes, Guerlain, Chaumet, TAG Heuer...). The show window decoration is also quite special.
One of the adjacent buildings, originally used as warehouse by “Le Bon Marché” and obviously also with Eiffel involved in the design, is today partly occupied by The Conran Shop, specialising in exclusive modern furniture and household goods.
In 1910, Mrs. Boucicaut (the husband died in 1877) had a big hotel, Lutetia, built on the other side of the square to accommodate travelling clients. This is still the only “palace” on the left bank. Considering the standard of the hotel, the customers did already then not all go to “Le Bon Marché” to buy cheap stuff.
In the immediate neighbourhood, there are some other interesting buildings including the “Missions Etrangères” (Foreign Missions) and the last home of Chateaubriand.