Guillaume Apollinaire (26 August 1880 – 9 November 1918) was a poet, playwright, short story writer, novelist, and critic of Polish descent. Born Wilhelm Albert WÅodzimierz Apolinary Kostrowicki in Rome, Italy. He emigrated to France in his late teens, adopted the name Guillaume Apollinaire, and soon became one of the most popular and important members of the artistic community in Paris.
As far I can find, Apollinaire’s posthumously published novel has not before appeared in English. Indeed rarely acknowledged, La Femme assise is not mentioned at all in thick Apollinaire books by, say, Francis Steegmuller and Margaret Davies.