Early Tenggren portrait of Rudolf Petersson discovered

Gustaf Tenggren: portrait of Rudolf Petersson,
fellow painting student, party pal and brother-in-law.

Now and then I get a letter with an image and an inquiry whether this is a real Tenggren painting or not. This time the attached jpg featured a portrait. I was quite happily surprised, as I immediately recognized the person. The focused young man with the white scarf and the ever-present pipe was Rudolf Petersson.

Rudolf Petersson from an unknown clipping, app. 1918.

To the main Tenggren fan he may not be familiar, but to some 3-4 generations of Swedes he is the originator of a well-known comic book hero, 91:an Karlsson. The comic strip started already in 1932 and has a large group of dedicated readers to this date, although Petersson himself died in 1970.

Rudolf Petersson at military service 1916.
Petersson got the inspiration for his comic book hero
91:an Karlsson from his time as a soldier.

Gustaf Tenggren and Rudolf Petersson, called Dolle, met when they both attended Valand school of Painting in Gothenburg in autumn of 1915. They became best friends, painting and partying together during the three years they spent at school. 

Gustaf Tenggren: a late drawing depicting his time at Valand school of painting in Gothenburg.
Rudolf "Dolle" Petersson is sitting next to the model.

The Petersson portrait was most likely made in 1916, possibly during a model painting session since Rudolf seems concentrating on depicting a motif. 

In September 1918 Gustaf married Rudolf’s sister Anna and so the two comrades even became brothers-in-law. 

Gustaf Tenggren married Anna Petersson on her birthday October 3rd, 1918. 

As Gustaf and Anna moved to Copenhagen in 1919, Rudolf joined them, living in their apartment. And when the couple left for USA and settled in Cleveland, OH in July 1920, Rudolf followed just the year after. They truly seemed inseparable.
In Cleveland, Rudolf quickly gained reputation as a talented cartoonist and caricaturist and worked for several newspapers, such as The Cleveland News and The Bystander.

Rudolf Petersson and famed jazz orchestra band leader,
Paul Whiteman showing a caricature for a poster
announcing a jazz concert at Keith’s Palace Theatre.
Cleveland News, 1920ies.

However, the friendship may have got chipped as Gustaf started to see another girl, Malin Froberg, who were later to be his wife. From that moment, Gustaf’s and Anna’s already withered marriage gradually fell apart, coming to an end as Gustaf and Mollie left for New York in 1923, leaving Anna and Rudolf in Cleveland. The Petersson siblings returned to Sweden in the thirties. Rudolf started drawing 91:an Karlsson and Anna re-married eventually. She kept an album of clippings about Gustaf all her life.

Rudolf Petersson in his studio 1963. By this time Petersson and
91:an Karlsson had become a part of the national cultural heritage.
The popular soldier even became a statue in Halmstad, Petersson's home town.

A 91:an Karlsson comic album from 1934, two years after its first appearance.

An 60-year anniversary album with the
original and the later version of 91:an Karlsson.

But Rudolf Petersson hardly ever spoke of Gustaf Tenggren later in his life. Maybe that is why the portrait was found in a junk shop in Oslo at the price of 50 Norwegian crowns, or a mere $10.