Career
His paintings often depicted Swedish landscapes and portraits. In 1915, Bergh became the director of the Swedish National Museum. After studying at the Royal Swedish Academy of Arts in Stockholm, Bergh traveled to France where he frequently visited the artist colony in Grez-sur-Loing.
Bergh produced several landscape paintings in Varberg from 1893 to 1896.
His father had also been a landscape painter. Bergh"s portraits of his friends have become his most enduring paintings.
One of them, Nordic Summer Evening (1889–1900), is his most frequently reproduced painting. During his career, Bergh painted portraits for Ellen Key, August Strindberg, Gustaf Fröding, Hjalmar Branting, and others
His 1905 portrait of Strindberg, Porträtt av August Strindberg, is one of his most famous paintings.
Bergh described Strindberg as "the most interesting model I have ever had. I read in his face, with its many lines of fate, as in a marvelous book" Bergh met Strindberg for the first time in 1889 and they soon became associates. A total of eighty-one letters Strindberg sent to Bergh during their friendship have been found, while twenty-six letters Bergh sent to Strindberg have been foundation
In the 1890s, Bergh established an art school at his atelier in Stockholm.
He became the director of the Swedish National Museum in 1915.