James died Friday at a Riverside, Calif., hospital after a battle with leukemia, her manager confirmed.
Born Jamesetta Hawkins, James grew up in California and founded a group called The Peaches. She was discovered by singer Johnny Otis, who had her sing "The Wallflower," which he wrote. It went to No. 1 on the R&B charts in 1955.
James signed with Chess Records in 1960, where she recorded "A Sunday Kind of Love" and "At Last" — perhaps her best-known hit (especially if you've been to a wedding any time in the last 20 years). Ironically, the song never cracked the top 10 on the R&B chart. In the 1970s, James entered rehab twice for drugs, but came back with 1988's Seven Year Itch. James had many health problems, leading her to have gastric-bypass surgery in 2003.
Throughout her career, James earned six Grammys and was voted into the Rock and Roll Hall of Fame in 1993. Her final television appearance was in April 2009 when she sang "At Last" on Dancing with the Stars. Her final album, The Dreamer, was released in November 2011.
James is survived by two sons, Donto and Sametto.