The Supremes | Biography & History | AllMusic

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On January 15, 1961, Berry Gordy signed the Supremes with Motown Records. From the article:

"The Supremes | Biography & History | AllMusic
Artist Biography by Richie Unterberger
The most successful American performers of the 1960s, the Supremes for a time rivaled even the Beatles in terms of red-hot commercial appeal, reeling off five number one singles in a row at one point. Critical revisionism has tended to undervalue the Supremes' accomplishments, categorizing their work as more lightweight than the best soul stars (or even the best Motown stars), and viewing them as a tool for Berry Gordy's crossover aspirations. There's no question that there was about as much pop as soul in the Supremes' hits, that even some of their biggest hits could sound formulaic, and that they were probably the black performers who were most successful at infiltrating the tastes and televisions of middle America. This shouldn't diminish either their extraordinary achievements or their fine music, the best of which renders the pop vs. soul question moot with its excellence.

The Supremes were not an overnight success story, although it might have seemed that way when they began topping the charts with sure-fire regularity. The trio that would become famous as the Supremes -- Diana Ross, Mary Wilson, and Florence Ballard -- met in the late '50s in Detroit's Brewster housing project. Originally known as the Primettes, they were a quartet (Barbara Martin was the fourth member) when they made their first single for the Lupine label in 1960. By the time they debuted for Motown in 1961, they had been renamed the Supremes; Barbara Martin reduced them to a trio when she left after their first single.

The Supremes' first Motown recordings were much more girl group-oriented than their later hits. Additionally, not all of them featured Diana Ross on lead vocals; Flo Ballard, considered to have as good or better a voice, also sang lead. Through a lengthy series of flops, Berry Gordy remained confident that the group would eventually prove to be one of Motown's biggest. By the time they finally did get their first Top 40 hit, "When the Lovelight Starts Shining Through His Eyes," in late 1963, Ross had taken over the lead singing for good.

Ross was not the most talented female singer at Motown; Martha Reeves and Gladys Knight in particular had superior talents. What she did have, however, was the most purely pop appeal. Gordy's patience and attention paid off in mid-1964, when "Where Did Our Love Go" went to number one. Written by Holland-Dozier-Holland, it established the prototype for their run of five consecutive number-one hits in 1964-1965 (also including "Baby Love," "Stop! In the Name of Love," "Come See About Me," and "Back in My Arms Again"). Ross' cooing vocals would front the Supremes' decorative backup vocals, put over on television and live performance with highly stylized choreography and visual style. Holland-Dozier-Holland would write and produce all of the Supremes' hits through the end of 1967.

Not all of the Supremes' singles went to number one after 1965, but they usually did awfully well, and were written and produced with enough variety (but enough of a characteristic sound) to ensure continual interest. The chart-topping (and uncharacteristically tough) "You Keep Me Hangin' On" was the best of their mid-period hits. Behind the scenes, there were some problems brewing, although these only came to light long after the event. Other Motown stars (most notably Martha Reeves) resented what they perceived as the inordinate attention lavished upon Ross by Gordy, at the expense of other artists on the label. The other Supremes themselves felt increasingly pushed to the background. In mid-1967, as a result of what was deemed increasingly unprofessional behavior, Ballard was replaced by Cindy Birdsong (from Patti LaBelle & the Bluebelles). Ballard become one of rock's greatest tragedies, eventually ending up on welfare, and dying in 1976.

After Ballard's exit, the group would be billed as Diana Ross & the Supremes, fueling speculation that Ross was being groomed for a solo career. The Supremes had a big year in 1967, even incorporating some mild psychedelic influences into "Reflections." Holland-Dozier-Holland, however, left Motown around this time, and the quality of the Supremes' records suffered accordingly (as did the Motown organization as a whole). The Supremes were still superstars, but as a unit, they were disintegrating; it's been reported that Wilson and Birdsong didn't even sing on their final hits, a couple of which ("Love Child" and "Someday We'll Be Together") were among their best.

In November 1969, Ross' imminent departure for a solo career was announced, although she played a few more dates with them, the last in Las Vegas in January 1970. Jean Terrell replaced Ross, and the group continued through 1977, with some more personnel changes (although Mary Wilson was always involved). Some of the early Ross-less singles were fine records, particularly "Stoned Love," "Nathan Jones," and the Supremes-Four Tops duet "River Deep -- Mountain High." Few groups have been able to rise to the occasion after the loss of their figurehead, though, and the Supremes proved no exception, rarely making the charts after 1972. It is the Diana Ross-led era of the 1960s for which they'll be remembered."