Pollock was born in Cody, Wyoming in 1912, the youngest of five sons. His parents, Stella May (McClure) and LeRoy Pollock, grew up in Tingley, Iowa. His father had been born McCoy but took the surname of his neighbors, who adopted him after his own parents had died within a year of each other. Stella and LeRoy Pollock were Presbyterian; the former, of Irish descent; the latter, of Scotch-Irish descent. LeRoy Pollock was a farmer and later a land surveyor for the government. Jackson grew up in Arizona and Chico, California. While living in Echo Park, California, he enrolled at Los Angeles' Manual Arts High School, from which he was expelled, after having been expelled from another high school in 1928. During his early life, he experienced Native American culture while on surveying trips with his father. In 1930, following his brother Charles Pollock, he moved to New York City where they both studied underThomas Hart Benton at the Art Students League of New York. Benton's rural American subject matter shaped Pollock's work only fleetingly, but his rhythmic use of paint and his fierce independence were more lasting influences.
Pollock was introduced to the use of liquid paint in 1936 at an experimental workshop operated in New York City by the Mexican muralist David Alfaro Siqueiros. He later used paint pouring as one of several techniques on canvases of the early 1940s, such as "Male and Female" and "Composition with Pouring I." After his move to Springs, he began painting with his canvases laid out on the studio floor, and he developed what was later called his "drip" technique, turning to synthetic resin-based paints called alkyd enamels, which, at that time, was a novel medium. Pollock described this use of household paints, instead of artist’s paints, as "a natural growth out of a need." He used hardened brushes, sticks, and even basting syringes as paint applicators. Pollock's technique of pouring and dripping paint is thought to be one of the origins of the term action painting. With this technique, Pollock was able to achieve a more immediate means of creating art, the paint now literally flowing from his chosen tool onto the canvas. By defying the convention of painting on an upright surface, he added a new dimension by being able to view and apply paint to his canvases from all directions. One possible influence on Pollock was the work of the Ukrainian American artist Janet Sobel. Sobel's work is related to the so-called "drip paintings" of Jackson Pollock. Peggy Guggenheim included Sobel's work in her The Art of This Century Gallery in 1945. The critic Clement Greenberg, with Jackson Pollock, saw Sobel's work there in 1946, and in his essay "American-Type' Painting" Greenberg cited those works as the first instance of all-over painting he had seen, stating that "Pollock admitted that these pictures had made an impression on him".