It didn't matter if it was five people on barstools in a northeast Minneapolis dive or an appreciative festival crowd in Europe. Willie Walker, the Twin Cities' finest soul singer, sang every performance as if it might be his last.

In the midst of a late-career resurgence in which he won recognition from several national blues organizations, Walker, 77, died in his sleep Tuesday morning at his St. Paul apartment after returning from a recording session in Oakland. The cause of death is unknown.

With a voice that was part velvet, part sandpaper, Walker offered a delectable combination of sweetness and sadness that epitomized Southern soul.

"To me, he was the greatest soul singer since Sam Cooke, who was his biggest hero," said Minneapolis musician Paul Metsa, who performed as a duo with Walker for the past nine years. "He was going to go to Chile on Thursday to headline a festival. In the last three or four years, the world finally realized how good he was. He got his due. And he couldn't have been more gracious about the accolades."

Sometimes billed as "Wee Willie Walker" for his 5-foot-5 stature, the natty soul man began his resurgence in the early 2000s when he hooked up with the Twin Cities' leading blues band, the Butanes, and recorded a series of well-received albums that brought him international attention.

More recently, a chance encounter led to renewed fame. About five years ago, blues harmonica star Rick Estrin was performing in Minneapolis and a friend invited him to see Walker at Shaw's, a bar in northeast Minneapolis.

"He couldn't believe that I could be in what he called 'a little dump like this'," Walker told the Star Tribune last year. "A few months after that I was a passenger on the Blues Cruise and did a whole show with [Estrin's band] Rick and the Nightcats and from that day on, I got some recognition."

It led to an Estrin-produced album in 2015, "If Nothing Ever Changes," and 2017's "After a While" with the Anthony Paule Soul Orchestra. He was named outstanding male blues singer at the Living Blues Awards last year.

In a Facebook post, Estrin called Walker a "genius. ... Willie could add his personal touch to a melody that just 5 minutes ago, sounded a little pedestrian and maybe semi-generic, and suddenly, it was transformed into something simultaneously majestic and heartbreaking. ... He belongs right in there with people like Johnnie Taylor, Sam Cooke, Billie Holiday, Frank Sinatra and George Jones."

Born in Mississippi and reared in Memphis, Walker cobbled together a career from a series of fateful and fruitful meetings. Having moved to Minneapolis in 1959 as a high school grad singing in gospel groups, he was at a laundromat one day when a guy said to him "You look like a singer." They hit it off and formed an R&B group called the Valdons, the first of many Twin Cities soul bands for Walker.

While gigging in the Upper Midwest, Walker got an opportunity to go home to Memphis to record several songs, three of which were issued as singles in 1968.

"The biggest — and worst — thing that happened in my life in music is when I recorded 'Lucky Loser,' and I get a call from Shreveport and it was John R," said Walker of the influential radio DJ. "He said, 'I want you to introduce your new song.' I didn't believe him. So when he got back on, I said, 'This is a [bleeping] joke.' " Click went the phone and Walker instantly realized his mistake. "That would have been my break. John R was a starmaker."

Instead, Walker worked a day job as a machinist to take care of his wife and children and performed on weekends.

Stardom "could have happened years ago had I pursued it," Walker reflected last year. "I was a young man with a family. I had all those questions about what's gonna happen that no one could answer."

"Willie was sweeter than honey from a bee," said Metsa, recalling how Walker once rented a pontoon for a ride for seniors at a White Bear Lake nursing home where he worked.

"He was just that kind of person, always wanting to do for other people," said his wife, Judy Walker. "If he could make someone happy, he'd go for it — even if he had to break the rules."

A memorial is being planned Dec. 22 at the Minnesota Music Cafe in St. Paul.