Sarah Blanche Sweet was an American silent film actress who began her career in the earliest days of the Hollywood motion picture film industry.
Born in Chicago, Illinois into a family of stock theater and vaudeville performers, Blanche Sweet entered the entertainment industry at an early age. At age 4 she toured in a play called The Battle of the Strong whose star was stage luminary Maurice Barrymore. A decade later Sweet would act with Barrymore's son Lionel in a Griffith directed film. In 1909, she started work at Biograph Studios under contract to director D. W. Griffith. By 1910 she had become a rival to Mary Pickford, also having started for Griffith the year before, which would result in Pickford leaving the studio intermittently. Sweet is renowned for her energetic, independent roles, at variance with the 'ideal' Griffith type of vulnerable, often fragile, femininity. After many starring roles, her first real landmark film was the 1911 Griffith thriller The Lonedale Operator. In 1913 she starred in Griffith's first feature-length movie, Judith of Bethulia. In 1914 Sweet was initially cast by Griffith in the part of Elsie Stoneman in his epic The Birth of a Nation but the role was eventually given to rival actress Lillian Gish, who was Sweet's senior by three years. That same year Sweet parted ways with Griffith and joined Paramount for the much higher pay that studio was able to afford.
Throughout the 1910s, Sweet continued her career appearing in a number of highly prominent roles in films and remained a publicly popular leading lady. She often starred in vehicles by Cecil B. DeMille and Marshall Neilan, and she was recognised by leading film critics of the time to be one of the foremost actresses of the entire silent era. It was during her time working with Neilan that the two began a publicized affair, which brought on his divorce from former actress Gertrude Bambrick. Sweet and Neilan married in 1922. The union ended in 1929 with Sweet charging that Neilan was a persistent adulterer.