Michael's publicist released a statement Sunday evening, confirming that the 53-year-old singer had died.
"It is with great sadness that we can confirm our beloved son, brother and friend George passed away peacefully at home over the Christmas period," the statement read. "The family would ask that their privacy be respected at this difficult and emotional time. There will be no further comment at this stage."
"Heartbroken at the loss of my beloved friend Yog," former Wham! member Andrew Ridgeley tweeted shortly after the news broke. "Me, his loved ones, his friends, the world of music, the world at large. 4ever loved. A xx"
On Monday, Sam Smith broke his Twitter silence to share how much Michael meant to him.
"@GeorgeMichael. Words can’t express how much you and your music meant and means to me," he wrote. "Please play his music as loud as you can today...& celebrate one of the most magical, talented, bravest & important figures in music & life as I know it. Your music & message will live on."
He added, "I would not be the artist I am if it wasn’t for you."
Other stars reacted publicly too. Their sentiments are below.