Willem Witsen had a wide circle of friends. Already at an early age, he was a board member of the painters association Saint Lucas and he founded De Nederlandse Etsclub (The Dutch Engraving Club). Of great importance was his association with the Eighties Movement, which wielded much artistic and even political influence at the end of the nineteenth century. There, he made the acquaintance of poets and writers such as Willem Kloos, Jacques Perk, Albert Verwey, Frederik van Eeden, Lodewijk van Deyssel and Herman Gorter. The magazine De Nieuwe Gids (The New Guide) was founded to propagate their ideas. Witsen availed himself of this opportunity as well, writing under a penname.

Next to these literary men, painters like George Hendrik Breitner, Isaac Israels and Jan Veth were among his closest friends. Witsen’s position in the Movement’s wide cultural network meant that he became a kind of pivotal figure among artists and writers in the 1880s. This is evidenced by the correspondence between him and nearly one hundred different individuals in the archives.