The painting "Singers in Haga" was executed in 1938, the same year the artist debuted at Konstnärshuset in Stockholm. The motif depicts a group of student singers performing in front of Prince Gustaf's Monument in the northern part of Haga Park. The location is carefully chosen as "the singing prince" Gustaf was the composer of "The Student Song" and several other songs.

Olle Olsson was familiar with the large and leafy Haga Park from an early age. For many years, the children of the idyllic township Hagalund had no school of their own, and makeshift classrooms were set up in the Copper Tents in the Haga Park. During recess, they played in the nearby stable and in the Echo Temple. Olle's father, Conny, was one of the members of the Solna Male Choir that sang in the park on Ascension Day.

The debut exhibition at the Royal Academy marked the beginning of a successful career. Early on, he added "Hagalund" to his signature to show pride in the place where he was born, lived, and worked – and which he fought to preserve throughout his life. Naïvist, expressionist, and romantic are terms often used to describe Olle Olsson Hagalund's art. He preferred to call himself a flâneur who throughout his life observed his surroundings in his beloved Hagalund.