bohemian (n.)
"a gypsy of society," 1848, from French bohemién (1550s), from the country name (see Bohemia). The modern sense is perhaps from the use of this country name since 15c. in French for "gypsy" (they were wrongly believed to have come from there, though their first appearance in Western Europe may have been directly from there), or from association with 15c. Bohemian heretics. It was popularized by Henri Murger's 1845 story collection "Scenes de la Vie de Boheme," the basis of Puccini's "La Bohème." Used in English 1848 in Thackary's "Vanity Fair."
The term 'Bohemian' has come to be very commonly accepted in our day as the description of a certain kind of literary gipsey, no matter in what language he speaks, or what city he inhabits .... A Bohemian is simply an artist or littérateur who, consciously or unconsciously, secedes from conventionality in life and in art. ["Westminster Review," 1862]