Amid all of the much-deserved ballyhoo regarding Bob Dylan’s 70th birthday last week, the celebration of another incredibly important event in music history was briefly delayed.

On May 21, 1971, Marvin Gaye’s groundbreaking album What’s Going On was released by Tamla Records, a Motown imprint. It was Gaye’s 11th studio album, and the first to credit him as the only producer. It was also the first album on which the Motown house band known as the Funk Brothers received a credit.

What’s Going On represented a complete departure from the radio-friendly pop music that brought so much success to Motown. Each of the album’s nine songs was part of a unified concept in which the socially conscious lyrics looked at the major issues of the day including poverty, drugs, civil unrest, ecology, and the Vietnam War.

When his singing partner Tammi Terrell died of a brain tumor in March, 1970, Marvin Gaye all but gave up the music business. He became depressed and refused to record or tour. At the time Obie Benson of the Four Tops and musician Al Cleveland were working on a song called “What’s Going On”. They asked Gaye to help them out with it. The plan was to have a Motown group called the Originals record it, but Benson and Cleveland convinced Gaye to record it himself.

Motown-founder Berry Gordy, Jr. wasn’t wrong often, but he was wrong about “What’s Going On.” When Gaye presented the song to him in June, 1970, Berry refused to release it, saying that it was far too politically outspoken. Motown had released other socially conscious records, like Edwin Starr’s “War,” and the Temptations “Ball of Confusion,” but Berry felt that “What’s Going On” went too far.

Gaye didn’t give up. He continued to lobby Berry for a release. Berry finally gave in and released the single in January, 1971. He was sure it would be a flop. It turned out to be the fastest selling single in Motown’s history to that point. It went to #1 on the R&B chart, and stayed there for five weeks, and climbed to #2 on the Pop chart.

Given the massive success of the single, Gordy called for an album from Gaye, and the singer responded with one of the most singular albums in music history. The songs on What’s Going On flowed from one to the next without interruption, which of course bothered Gordy since it created a problem for radio programmers. That cohesive sound however is one of the things that makes the album so special.

While the title track of the album took on the Vietnam War, “Flyin’ High (In the Friendly Sky)” addressed drug abuse, “God Is Love” (the flip side of the “What’s Going On single) was a song of faith, “Inner City Blues (Make Me Wanna Holler)” a powerful attack on poverty, and “Mercy Mercy Me (The Ecology)” an early environmental anthem.

What’s Going On remained on the Billboard Pop Albums Chart for over a year, and had sold two million copies by 1972. In 2003 it was ranked #6 in Rolling Stone’s 500 Greatest Albums of All Time list, and a critics poll conducted by the British newspaper The Guardian called in “the greatest album of the 20th century.”