55 years ago today, the first human ever traveled in space.

Russian cosmonaut — the astronaut version for the Russian Space Agency — Yuri Gagarin was only 27 when he made his historic 108-minute orbital flight in the Vostok 1 spacecraft on April 12, 1961. To mark Gagarin’s remarkable journey to space, the United Nations declared today International Day of Human Space Flight. He quickly rocketed to stardom as his face was plastered on the front page of newspapers worldwide.

When he returned to earth, there was a massive parade and Gagarin stood side by side with Nikita Khrushchev, Premier of the Communist Soviet Union. “The face of a people whose leaders would wipe out democracy,” solemnly proclaimed an American newscaster at the time.

Here’s how it went down:

Before the parade, though, there was the mission:

Around 9 a.m. on the day of the launch, Gagarin sped off from Baikonur space station in the Vostok 1 — an approximately 10,400-pound nearly spherical cabin covered with vaporizable material. Gagarin stared down at Earth from the three small portholes of the vessels, relying only on the radios, a life-support system, and an ejection seat during his journey. After making one complete orbit around Earth, Vostok 1 began its descent and landed in Kazakhstan just one hour and 28 minutes from the initial launch.

The Soviet Union was quick to use Gagarin as a propaganda puppet, flaunting him like a modern day celebrity. But Gagarin came from tough beginnings. In a 1998 article, The Guardian reported that in 1942 during Germany’s occupation of Russia, eight-year-old Gagarin remembered “going down into the cellar to find bread, potatoes, milk, and vegetables, and distributing them to refugees from other districts.” It’s also reported that Gagarin had sabotaged German tanks and shoved those very potatoes into exhausts of Nazi military cars.

Gagarin's face was in papers everywhere.

Perhaps just as fascinating was Gagarin’s death — his life was cut short at only the age of 34. He was killed just seven years after his famous mission to space in a routine test flight in a MiG-15 fighter on March 27, 1968. He and his co-pilot suddenly plummeted from 10,000 feet into a forest below, killing both pilots on impact. An assortment of conspiracy theories have been put forth: Gagarin was drunk on vodka during the flight, or he was set up by Soviet leader Leonid Brezhnev. Reports claimed Brezhnev wasn’t a big fan of the cosmonaut.

Many have tried to clear the haze around Gagarin’s death. Alexei Leonov, the first man to leave a spacecraft and float in outer-space, spoke out in 2013 about a report that confirmed an unauthorized jet had flown dangerously close to Gagarin’s plane, causing it to crash.

In 2010, a retired Soviet air force colonel, Igor Kuznetsov, told the Telegraph that Gagarin noticed an open vent creating a dangerous environment at 10,000 feet so he and his co-pilot followed emergency procedures to descend to a safer altitude. However, the plane ended up in a nose dive, causing the pilots to lose consciousness and crash. Kuznetsov said he found documents that show pilots had been in the plane prior to Gagarin and could have carelessly left the vent open.

“Nobody knows what really happened except us,” Kuznetsov told The Telegraph. “We need to tell our people and the international community the real reason why the world’s first cosmonaut died.”

While we may still ponder over the mysteries of his tragic death, people around the world celebrate Gagarin’s accomplishments. Russia even created an incredible portrait of Gagarin on a frozen lake in the Ryazan region on Monday:

Photos via NASA/Flickr, ITU Pictures/NASA/Flickr