"Mobile Suit Gundam" is set in the Universal Century timeline, a futuristic era where humanity has colonized space, establishing settlements known as space colonies. The Earth Federation governs these colonies, but tensions rise as the Principality of Zeon, a breakaway faction, declares independence. The conflict escalates into a full-scale war, known as the One Year War, between the Earth Federation and Zeon. Zeon employs advanced humanoid weapons called Mobile Suits, which quickly dominate the battlefield.

The story begins with the Zeon forces attacking Side 7, a neutral colony, to destroy a prototype Federation Mobile Suit, the RX-78-2 Gundam. Amuro Ray, a young civilian, stumbles upon the Gundam and pilots it to defend his home. His natural aptitude for piloting the advanced machine becomes crucial as he joins the Federation's White Base, a prototype warship carrying refugees and military personnel. The crew of the White Base, including Captain Bright Noa, navigator Mirai Yashima, and mechanic Ryu Jose, becomes a makeshift family as they face relentless attacks from Zeon forces.

Amuro's journey is marked by his growth from an inexperienced teenager to a skilled pilot, grappling with the psychological toll of war. His primary adversary is Char Aznable, a cunning and enigmatic Zeon ace pilot known as the "Red Comet." Char's motivations are complex, driven by personal vendettas and a desire to dismantle the corrupt Zabi family, who rule Zeon. The Zabi family, including Gihren, Kycilia, and Dozle, are central antagonists, each wielding power and influence over Zeon's military strategies.

As the war progresses, the White Base crew engages in numerous battles, from space skirmishes to ground assaults on Earth. The Gundam's superior technology and Amuro's growing skills make them a formidable force, but the cost of war weighs heavily on the characters. Key events include the Battle of Odessa, the defense of Jaburo, and the final confrontation at A Baoa Qu, where the fates of both factions are decided.

Themes of sacrifice, the horrors of war, and the impact of technology on humanity are woven throughout the narrative. Characters like Sayla Mass, Char's estranged sister, and Ramba Ral, a Zeon commander with a sense of honor, add depth to the story. The series concludes with the end of the One Year War, but the consequences of the conflict leave lasting scars on the characters and the world they inhabit. "Mobile Suit Gundam" is a foundational work in the mecha genre, blending personal drama with large-scale warfare and setting the stage for numerous sequels and spin-offs.