Given his career-long stance in favor of female empowerment, it's somewhat fitting that Prince often covered songs recorded by women. In addition to Joni Mitchell's "A Case of You" and Joan Osbourne's "One of Us," he also cut "I Can't Make You Love Me," a ballad that Bonnie Raitt took to the Top 20 in 1991.

His cover came out on Emancipation, his 1996 triple-disc collection that ushered in a new free-agent era after his prolonged and contentious battle with Warner Bros. While its appearance -- along with "One of Us" on the same album -- may have seemed like a simple recognition of a recent song he liked, the lesser-known reality is that he and Raitt had worked together nearly a decade before.

After spending the '70s making acclaimed-but-moderate-selling records (coincidentally, also for Warner Bros.), by the mid-'80s, Raitt was without a label. Needing to rebuild her career, she quit drinking, and then she got a call in November 1986 from Prince.

“He said, ‘It was unfortunate you were treated that way and would you like to come and do some songs together at Paisley Park? I really appreciate women artists and I’ve always admired you,’” she recalled to the Star Tribune in 2016. “I was looking at several offers and I didn’t know if it would be a good fit for me and I didn’t want to necessarily make a commercial dance hit or have that kind of profile. I said, ‘If we could meet in the middle and just so you know that I’m not coming over to be produced by you and be a pawn in your playground. If it can be a real collaboration, then I’d like to do it.’”

"It was interesting to see what he would come up with," she told the Chicago Tribune in August 1987, "especially because I`m political and not a very shy person, and he`s not very political and he is very shy. But the fact that we both do R&B, and now that I`ve heard the songs, it makes complete sense to me. It came out really well."

"It was nice to be working with another singer and guitarist," Raitt continued. "There was a lot of mutual respect. There isn`t any danger of his steamrolling me into his own image. I`m strong enough personality-wise so I`m not going to be told how to sing. He was not any more demanding than I was of myself."

Years later, however, she had a different perspective on the tracks. “I appreciated the enthusiasm, but they were not in my key,” she said. “The topics were not things I was comfortable singing. It was something like ‘You can mess me around all over town / But we’re still cool / I like being your fool.’ That’s not something I’d sing. He was guessing about the lyrics. I loved the tracks but because I wasn’t there I said, ‘We’re going to have to reconvene.’ ... They were four or five keys lower than what I sing."

They never reconvened, and the songs never came out. According to the Chicago Tribune, she put vocals and lead guitar to three tracks -- two R&B and one reggae -- that he created, although PrinceVault only has details about two of them. Both "I Need a Man" and "Promise to Be True" stemmed from his work with Vanity 6. The former was written in 1981 for the Hookers, the pre-Denise Matthews version of the group, while the latter was slated for their second record, but the split between Prince and Matthews resulted in the end of that group.

Still, Raitt said the time working with him was "a lot of fun. He couldn’t have been nicer” and they remained in touch over the years. And as it turns out, she bounced back without his help. She signed with Capitol and, in 1989 released Nick of Time, which topped Billboard's album chart, won five Grammys and sold five million copies. Eighteen years after her debut, she had finally achieved the stardom she deserved.

"I Can't Make You Love Me" appeared on the follow-up, 1991's Luck of the Draw. Written by Allen Shamblin and former pro football player Mike Reid, Raitt called it "one of the most honest and original heartache songs I had ever heard. It was a point of view that I had been on both sides of, and it struck me deeply."

Millions agreed with her. With the help of Bruce Hornsby on piano, it reached No. 18 on the Hot 100 and No. 6 on the Adult Contemporary chart, and Luck of the Draw outsold Nick of Time. "It’s meant so much," she continued, adding that "of all the songs I’ll ever be associated with, the number of people -- of all races, all ages, all musical genres -- that come up to me and almost tear up talking about what that song means to them, that’ll make it the greatest gift I’ve ever had musically."

Prince's cover, re-titled "Eye Can’t Make U Love Me" in his style (with a representation of an eye at the beginning), kept the arrangement sparse, but added a heavy dose of '70s Philly soul, including an electric sitar, background vocals, Eric Leeds' saxophone and a lead vocal that wavered in-and-out of his falsetto (he must have been thinking a lot about that era during the Emancipation sessions; he also covered the Stylistics' "Betcha By Golly Wow!").

Hear Prince Perform "Eye Can't Make U Love Me"

But although Raitt called his version "very beautiful," there was one particularly '70s-inspired part of Prince's take that bothered Raitt's producer Don Was -- the seductive breakdown.

"He’s such a great singer and you can marvel at the technique," he told Stereogum, "but then he gets to the vamp and he says something like 'Come here, baby, I am going to sex you up,' or something like that. He’s got no idea what the song is about. I have never heard a guy who can sing it. I don’t know if a guy can sing the song."

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