Baron Carl Nils Daniel Bildt (Stockholm 1850 - Rome 1931) was a Swedish diplomat and historian. He is known for his archival research and studies of topics in Swedish history relating to Rome and Italy, and in particular of Saint Bridget of Sweden and Queen Christina. His publications include Anteckningar från Italien av en svensk diplomat (Stockholm 1896), Svenska minnen och märken i Rom (Stockholm 1900), Les médailles romaines de Christine de Suède (Rome 1908). Carl Bildt’s book collection was donated to the Swedish Institute of Classical studies in Rome in 1931. The collection includes literature on Saint Bridget, Queen Christina of Sweden, King Gustav III of Sweden, and cultural relations between Sweden and Italy. In 1998 the Bildt family donated a collection of binders with newspaper clippings (1891-1937) to the Swedish Institute alongside 25 volumes of diaries (1885-1931) that belonged to Carl Bildt’s wife Alexandra Keiller Bildt (1864-1948). The donation also comprised a collection of letters (1875-1883) to Carl Bildt from his first wife Lilian Moore Bildt (1853-1911), her mother Clara Jessup Moore (1824-1899), and her brother Clarence B. Moore (1852-1936).