Cummings first published "i was sitting in mcsorley's" in his collection Tulips & Chimneys, which appeared in 1923. It has also been anthologized in The Norton Anthology of Modern Poetry. Different versions of the poem have been printed over time.

The poem is set in McSorley's Ale House, where cummings frequently drank. It is a New York City saloon on East Seventh between Second and Third Avenues. Known as a favorite haunt of bohemians and artists, McSorley's opened in 1854, and both Abraham Lincoln and John F. Kennedy are said to have visited the saloon. In the poem, the speaker, alternately meditative and descriptive, depicts his experience inside the saloon in typical cummings fashion, using nouns as verbs and vice versa, coining portmanteau words (words whose form and meaning are derived from a blending of two or more distinct forms), twisting syntax, and fragmenting words. The poem visually resembles prose, with its division into twelve paragraph-like sections.

Like many of the other poems in Tulips & Chimneys, "i was sitting in mcsorley's" embodies the opposition between the organic, natural world, and human society, what cummings refers to as "manunkind." Cummings's description of the bar is thick with sensuous and concrete images and effectively conjures the feel, smell, and sight of a saloon. The descriptions themselves also mimic the often sloppy way the brain processes perceptions and produces language when affected by alcohol.

Cummings's love for the city and his revulsion of humanity are both evident here.