Eden Prime is the first planet outside of the sol system to be colonized by Humans. It's considered as one of the biggest achievements in human history and proved that humans can make new colonies away from Earth. The Humans move to Eden Prime was met with criticism from the other races who believed the Humans were foolish to colonise so close to the dangerous Terminus Systems.
The climate on Eden Prime is very similar to Earth. It's covered in plants and green fields which attracts farmers who are looking to take advantage of the planet's fertility.
 Geth Attack
After human scientists discovered a Prothean Beacon on Eden Prime, this news quickly made it's way to Saren, who sent an army of Geth to the Planet to recover it. The residents of Eden Prime were completely unprepared for the attack. Luckily, they were able to send a distress call to the SSV Normandy that was nearby. Captain Anderson sent Commander Shepard, Lieutenant Alenko, Corporal Jenkins and Nihlus Kryik down to the planet to help the residents.
Jenkins was killed early in the mission and Nihlus was murdered by Saren. Commander Shepard added Gunnery Cheif Ashley Williams to his squad after saving her from a Geth attack. Once Saren had taken what he needed from the Prothean Beacon, he set charges around the Beacon to destroy any evidence of him being there. However the Normandy crew reacted faster than Saren has expected and were able to deactivate the charges that would eventually lead to Saren's downfall as a Spectre.