Chaja (Klara) Ringelheim (later Chaja Rosenfeld, Chaja Rosenzweig, and finally, Claire Rosen) is the daughter of Jacob and Miriam (Reich) Ringelheim. She was born December 5, 1911 in Jaroslaw, Poland. Chaja had three brothers: David (b. 1906), Shimon (Sidney, b. 1907) and Josef (b. ca. 1921-22). Chaja's father, Jacob, had immigrated to the U.S., where he was naturalized on May 5, 1903. The following year, he was joined by his younger brother Benjamin, who was naturalized in 1913 and remained a resident of the U.S. for the rest of his life. Jacob returned to Poland in 1904 or 1905, settling in Jaroslaw. There, he married Miriam Reich and raised three children. Together with his brother-in-law Nathan, Jacob ran a flour mill and possibly also a marmelade factory. Jacob returned to the U.S. in May 1916 following a violent incident at the flour mill. He returned to Poland in 1920 or 1921. His two sons, David and Shimon, immigrated to the U.S. in 1924. The rest of the Ringelheim family moved to Przemysl in the early to mid-1930s. Jacob eventually acquired co-ownership of a brick factory and several apartment houses. Hitler's rise to power was a source of great concern to Jacob. Already in 1934 he wrote to his brother Benjamin in the U.S. that he was worried about the impact of the Nazi regime on the political stability of Poland, and was considering returning to America with the rest of his immediate family. However, the difficulty of liquidating his assets in Poland seems to have prevented him from doing so. Chaja started to work for her father as a bookkeeper in the brick factory in 1932 and continued in that capacity until the end of 1937. In August 1937 she married Henryk Rosenfeld, the son of Chaskiel and Ernestyna Rosenfeld from Jaroslaw. The following year the couple left for Pisa, Italy, where Henryk began or continued medical school. Soon after the outbreak of World War II, Henryk decided to return to Poland. Chaja's mother tried to get her permission to return to Poland, but did not succeed. Consequently, Chaja remained in Italy, and on April 13, 1940 was issued an American passport in Genoa (on the basis of her father's American citizenship). She immigrated to the U.S. shortly thereafter. Her parents and brother Josef were killed in Sambor, Ukraine in 1943. Henryk was also killed in 1943 near Przemysl. Chaja was living and working in the United States when she received a letter from Markus Rosenzweig, a Polish Jew from Krakow, who had survived the war as a member of the Anders Army. He invited her to come to London to meet with him. He was single, and when he learned that Chaja was a widow it seemed as if it might be an opportunity for them both. She sailed to London on the SS St. Mary in 1948, and on January 22, 1949 Chaja and Markus were married. The wedding took place in Paddington, England, and the couple moved later that year to the United States. In 1951, when Markus was naturalized as an American citizenship, they formally changed their names to Marcus and Claire Rosen.