Correspondents, Interlocutors, Mentors and Dramatis Personae

Vladimir Onufrievich Kovalevskii (1842–1883) 
co-conspirator, husband and friend

came from a Russian–Polish land-owners’family. He got involved in the Russian radical circles and was the first to translate andpublish Darwin’s work in Russian. 
husband and friend

Alexander Kovalevsky (1840-1901)

He was  an embryologist, who studied medicine at the University of Heidelberg and became professor at the University of St Petersburg. He was Sofia's brother-in-law and they corresponded frequently.
You see, I have been made into a princess too! They would be better to assign me a salary. Well, yes, perhaps they will do that too 
[SK to AK, December 1883]
Sofia Vladimirovna Kovalevskaya (Fufa) (1878–1952). 
daughter
After her mother’s death Fufa lived in Stockholm with family friends, until she finished secondary school and then returned to live with Iulia Lermontova, Sofia’s friend, in Russia. She became a doctor and worked for the Red Cross in Russia and abroad. After her retirement she became a medical librarian and translator and she got very much involved in publishing her mother’s literary work.
Vasily Korvin-Krukosky(1803-1875)
father
Russian general who looked after Sofia's education in mathematics and funded Sofia's and her sisters studies and travels in Europe.
Anna Vasilyevna Korvin-Krukovskaya, Jaclard  (1843–1887) 
Sister, correspondent
She was a socialist and feminist revolutionary. After following her sister Sofia in Europe, she eventually settled in Paris where she metVictor Jaclard, whom she eventually married. She got heavily involved in the Paris commune and was exiled after its fall.
Iulia Lermontova (1847–1919) 
She was Sofia’s close friend and the first woman inthe world to get a PhD in Chemistry from the University of Göttingen in 1874. She became Fufa's godmother and looked after her after her mother's death.
Gösta Mittag-Leffler (1846–1927) 
promoter, mentor, correspondent and friend
He was a Swedish mathematician, who founded the journal Acta Mathematica and the Mathematics Institute of the Swedish Academy of Sciences that bears his name. He promoted Sofia's academic position in Stockholm and invited her to the editorial board of the Acta Mathematica.
What most deeply interested me in St Petersburg was getting to know Madame Kovalewsky. Today [10 February 1876] I spent several hours at her house. As a woman, she is delightful. She is beautiful and when she speaks, her face illuminates with such an expression of feminine kindness and superior intelligence, that the effect is dazzling. Her manner is simple and natural without the slightest trace of pedantry or pretence. She is in all respects a complete ‘woman of the high world’. As a scholar she is characterized by her unusual clarity and precision of expression. The depth of her knowledge becomes clear then and I understand fully why Weierstrass considers her the most gifted of his students. [Weierstrass et Sonja Kowalewsky, 172]
Anna Carlotta Leffler(1849-1892)
friend, correspondent co-writer and biographer
She was a Swedish author, sister of Gösta Mittag-Leffler and Sofia's friend and confidante. They wrote a theatrical play together and she was her first biographer.
Alexander Nikolayevich Strannolyubsky(1839-1903)
tutor
He was a wellknown teacher of mathematics and a strong proponent of higher education for women 
Many years later when I was already fifteen, I took my first lesson in differential calculus from the eminent Petersburg professor Alexander Nikolayevich Strannolyubsky. He was amazed at the speed with which I grasped and assimilated the concepts of limit and of derivatives.( A Russian Childhood, 123)
Karl Weierstrass (1815-1897) 


He is often cited as the father of modern analysis. He became a professor of mathematics in Berlin, without finishing his university degree and perhaps his unorthodox academic career might have influenced his willingness to take up Kovalevskaya’s supervision outside the formal university procedures.  
It is true that I regret somewhat that I did not choose from the first to lecture on the calculus of variations […] But please, be so kind, my dear best friend, and help me by giving me your advice in my distress. [Deine Sonya, 27]