Brown died Friday of complications from a stroke and heart attack at a Las Vegas-area hospital, said Lindajo Loftus, a publicist for the Rhythm & Blues Foundation, which Brown helped establish. She was 78.

“Ruth was one of the most important and beloved figures in modern music,” Bonnie Raitt said in a statement.

“You can hear her influence in everyone from Little Richard to Etta (James), Aretha (Franklin), Janis (Joplin) and divas like Christina Aguilera today.”

“She was my dear friend and I will miss her terribly,” Raitt said.

Brown shot to stardom in 1949 when her recording of the ballad “So Long” became a hit. Her soulful voice produced dozens of hits for Atlantic Records, cementing the then-fledgling label’s reputation as an R&B powerhouse.

Trained in a church choir in her hometown of Portsmouth, Va., Brown sang a range of style from jazz to gospel-blues in such hits as “5-10-15 Hours” and “Teardrops in My Eyes.”

But as R&B fell out of style in the late 1950s and other artists took over the charts, Brown was forced to find other work. She worked as a maid, school bus driver and teacher to support herself and her two sons for the next decade and a half.

Brown enjoyed a career renaissance in the mid-70s when she began recording blues and jazz tunes for a variety of labels and found success on the stage and in movies.

She won acclaim in the R&B musical “Staggerlee” and won a Tony Award for best actress in the Broadway revue “Black and Blue.”

She also played a feisty deejay in the 1988 cult movie “Hairspray.” A year later, she won a Grammy for best jazz vocal performance for the album Blues on Broadway.

Brown continued to perform and record in her later years, becoming a popular host of National Public Radio’s “Harlem Hit Parade” and “BluesStage.”

She was inducted into the Rock and Roll Hall of Fame in 1993.

She became a prominent advocate for the rights of aging R&B musicians during her long struggle to recoup her share of royalties from Atlantic. Her effort led to the formation of the Rhythm & Blues Foundation, a Philadelphia-based nonprofit dedicated to providing financial and medical assistance, as well as historical and cultural preservation of the musical genre.