Childish Gambino's searing 'This is America' has become the first hip-hop track to win a Song of the Year Grammy, while Drake made a surprise appearance and Lady Gaga dominated the early awards.
Kacey Musgraves took home the coveted Album of the Year award at the star-studded event.
'This is America', about police brutality and racism, also took Grammys for Best Music Video and Best Rap Performance. But Gambino, the musical alter ego of actor Donald Glover, was not at the show to celebrate the milestone.
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Rappers Kendrick Lamar and Jay-Z were also absent from the biggest honours in the music industry. But Canada's Drake, who had been expected to stay away, turned up to collect the Grammy for Best Rap Song for 'God's Plan'.
The Grammys has frequently shut out hip-hop artists from its top prizes, despite rap's dominance as the biggest music genre in the United States.
But Drake, the biggest streaming artist of 2018, told musicians not to worry about winning prizes.
"The point is you've already won if you have people who are singing your songs word for word, if you're a hero in your hometown," he said in his acceptance speech.
"If there's people who have regular jobs who are coming out in the rain and the snow and spending their hard earned money to buy tickets to come to your shows, you don't need this right here, I promise you."
Drake, Post Malone and Cardi B, are also up for the coveted Album of the Year award, which will be announced at the end of the evening.
Outspoken Cardi B, whose personal life and hit records have dominated pop culture for the past two years, turned in a raunchy performance of 'Money' dressed in a black mesh and silver body suit.
Lady Gaga's hit song 'Shallow' from the movie A Star is Born won two Grammys, while the musician-turned actress took a third Grammy home for her 'Joanne (Where Do You Think You're Going)', which won for pop solo performance.
Already a show with a strong line-up of female performers and nominees, the Grammys sprung another surprise by including former US first lady Michelle Obama in an opening that also featured Lady Gaga, Jennifer Lopez, actress Jada Pinkett Smith and host Alicia Keys talking about the power of music.
"From the Motown records I wore out on the [Chicago] Southside to the 'Who Run the World' songs that fueled me through this last decade, music has always helped me tell my story," Ms Obama told the cheering celebrity audience in Los Angeles.
Cuban-born Camila Cabello kicked off the televised show with a dance heavy performance of her hit single 'Havana' with Latin artists J Balvin, Ricky Martin and Young Thug.
Keys, Gaga, Dolly Parton, Miley Cyrus, Janelle Monae, Diana Ross, Katy Perry and Best Country Album Grammy winner Kacey Musgraves also performed.
Folk singer Brandi Carlile, 37, took three early Grammys while an absent Ariana Grande, who pulled out of the show last week after a dispute with producers, won her first Grammy, Best Pop Vocal album for Sweetener.
"This is wild and beautiful. Thank you so much," Grande tweeted.