Sonja Branting-Westerståhl was one of the first female lawyers in Sweden. She was the seventh woman to be elected to the Advokatsamfundet (Swedish Bar Association) in 1927. She was also a committed member of the Swedish Social Democratic party and active on behalf of women’s issues.

Sonja’s father was the prominent social democrat and later prime minister Hjalmar Branting and her mother was the author and journalist Anna Jäderin, subsequently Anna Branting. Her parents married in 1884 and had two children, Georg and Sonja Branting. The family also included children from Anna Branting’s earlier marriage to the soldier Georg von Kraemer, namely Vera and Henry von Kraemer.

Sonja’s parents’ civic participation was adopted by both Sonja and her brother Georg, who later also became a lawyer, albeit in slightly different ways. Sonja Branting grew up in Stockholm, graduated from the Palmgren school in 1909 and then began to study law. In 1914 she married the lawyer Olof Westerståhl and two years later she gave birth to their son Jörgen, who later became a famous political scientist. The same year, 1916, she completed her law degree.

From 1918 to 1925 Sonja Branting-Westerståhl worked at the Stockholm city legal aid institution. In 1927 she and her husband set up a joint legal office in Stockholm. She came to specialise on negotiating matrimonial disputes as decreed in the new marriage law enacted in 1920. From 1933 to 1960 she was officially appointed as arbitrator in Stockholm city. She was much trusted and highly esteemed for her skill, her dedication and her social empathy. When her husband died in 1948 she continued the legal office on her own and expanded it.

Sonja Branting-Westerståhl was, like many of her female legal colleagues, deeply committed to the women’s issues of the time. It not only influenced her legal work but also her wider social activism. She was a social democrat and mainly active in Social Democratic Women in Sweden, where she was a board member from 1936 to 1952. For a short time in 1948 she was also a substitute member of the second chamber in parliament.

During the 1930s and 1940s Sonja Branting-Westerståhl was very active in anti-fascist and anti-Nazi campaigns. Along with her brother Georg she was one of the leaders of the so-called Spanienhjälpen (Swedish committee for supporting Spain). In 1935 she undertook a lengthy lecture tour of the USA where she spoke out against fascism and dictatorship. She also visited the republican faction in Spain during the civil war there and inspected the Spanish refugee camps in France and Africa as international delegate.

Sonja Branting-Westerståhl died in 1981.