Just four short days after the Parkland, Florida, shooting, a group of the survivors announced the event that would soon become one of the largest protests in American history: March For Our Lives. Student organizers from the Never Again movement planned the march in collaboration with the nonprofit organization Everytown for Gun Safety.

The main event was held in Washington, D.C. on March 24, where an estimated 200,000 to 800,000 people gathered in support of gun reform. And all over the world, there were over 800 sibling marches taking place at the same time. The overall turnout was an estimated 1.2 to 2 million people.

Marjory Stoneman Douglas students Cameron Kasky, David Hogg, Delaney Tarr, Sarah Chadwick, Alex Wind, Jaclyn Corin, Ryan Deitsch, Aalayah Eastmond, and Sam Fuentes all delivered speeches at the march, the most notable and widely spread on social media being delivered by one of the most prominent leaders of the Never Again Movement Emma González.

González spoke and made sure to name all 17 of the victims of the shooting, but the most significant part of her speech was not what she said, it was what she didn’t say. For over 4 minutes, González stood still, silently staring into the crowd. When an alarm went off signifying that the speech had hit six minutes and 20 seconds, the amount of time that the Parkland shooting lasted, she spoke again.

“Since the time that I came out here, it has been 6 minutes and 20 seconds, the shooter has ceased shooting, and will soon abandon his rifle, blend in with the students as they escape, and walk free for an hour before arrest. Fight for your lives before it’s someone else’s job,” González said.

Naturally, the march garnered some disapproval from politicians, namely members and supporters of the NRA. The students were publicly criticized in the news and on social media, and there were even doctored images posted online depicting González tearing apart a copy of the Constitution when it was really a shooting target, part of the demonstration.

Despite this negative backlash, the movement has gained massive support from celebrities, including singers Ariana Grande, Lin-Manuel Miranda, Ben Platt, Miley Cyrus, Jennifer Hudson, Selena Gomez, Lady Gaga and Demi Lovato who all joined the march.

George Clooney, Oprah Winfrey, Steven Spielberg, and Gucci each independently donated $500,000 to the movement, while Chrissy Teigen and John Legend also donated $25,000. Taylor Swift also donated, James Corden promoted the cause, and Jimmy Fallon pledged to attend with his family. Other big-name supporters of the march included Justin Bieber, Paul McCartney, and the Kardashian family.

Former President Barack Obama even spoke out about the march, saying how inspired he was by the students who made March for Our Lives possible.

“Keep at it. You’re leading us forward,” Obama said in a tweet. “Nothing can stand in the way of millions of voices calling for change.”