Walburga Stemmer (March 1892–October 1928) was a woman who had an affair with Erwin Rommel and gave birth to his daughter, Gertrud Stemmer (later Mrs. Gertrud Pan), on December 8, 1913. Rommel's family put pressure on him to leave her and return to his fiancée Lucie Mollin, whom he soon married.
Stemmer died in 1928, when Rommel's wife Lucie was pregnant with the couple's son Manfred. Her cause of death was given as pneumonia, though it is generally accepted that she probably committed suicide.
Stemmer was the daughter of a seamstress. She was twenty years old and working as a fruit-seller in Weingarten (Württemberg) when she met Rommel, who was assigned to the area to train army recruits. He was separated from his fiancée Lucie, who was studying in Danzig.
In 1913, a year after he met Walburga, their daughter Gertrud was born, to Rommel's delight. He wrote to Walburga, calling her his "little mouse". He said he would like to set up home with her and Gertrud: "It's got to be perfect, this little nest of ours." However this did not happen. Rommel broke off the relationship. Walburga is said to have never recovered. Rommel's mother seems to have put pressure on him to end the relationship because she believed Walburga was not suitable to be the wife of an officer. 
Despite the separation, Rommel had no intention of abandoning Walburga and Gertrud. He told Lucie the truth about the relationship, provided financial support and kept in regular contact. When World War I began only a few months after Gertrud's birth, Rommel arranged that in the event he was killed his life insurance would support Gertrud.
In 1916 Rommel married Lucie. Walburga continued to hope that he would return to them. She hoped that as long as the couple remained childless Rommel's devotion to Gertrud would bring him back to her. According to Gertrud's son Josef Pan, "Rommel was Walburga's only love. As long as Rommel and Lucie never had children she held on to the conviction that he would return to her. When Manfred was born in 1928 she took an overdose... The explanation given in public was that she had died of pneumonia. Later the family doctor told my mother she had taken her own life."
Gertrud and Rommel
After her mother's death, Rommel and Lucie helped to look after the fifteen-year-old Gertrud. Gertrud exchanged hundreds of letters with her father. She knitted him a plaid scarf, which is seen in many images of Rommel in the desert. Lucie knew that Gertrud was Rommel's daughter and the family helped support her. Manfred Rommel notes she was always referred to as "cousin Gertrud".
She was a frequent visitor to the family and was at Rommel's hospital bedside after he returned ill from Africa. There, she answered the telephone when a furious Hitler ordered him back to Africa. She stayed close to the family even after her father's death. The letters among Rommel, Walburga and Gertrud were inherited by Gertud's son Joseph, who made the story public in 2000 after Gertrud's death.
- Caddick-Adams, Peter, Monty and Rommel: Parallel Lives, Arrow, 2012, pp.23-4.
- Humanities & Social Sciences Online, Cole, Mark, review of Dennis Showalter. Patton and Rommel: Men of War in the Twentieth Century. New York: Berkley Caliber, 2005. 441 pp. $16.00 (paper), ISBN 978-0-425-20663-8; $24.95 (cloth), ISBN 978-0-425-19346-4.
- Maurice Philip Remy, Mythos Rommel, List, 2002.
- The Battle of Alamein: Turning Point, World War II, by Bierman and Smith (2002). ISBN 0-670-03040-6
- Biography of Rommel on Channel 4 in part describing his relationship with Stemmer
- German article about Rommel's and Stemmer's family history