From Halopedia, the Halo wiki
The Rainforest Wars (sometimes rendered as Rain Forest Wars) were a nineteen-month-long series of bloody conflicts between Koslovic and Frieden forces in South America from February of 2162 to September of 2163.
In 2162, following the Jovian Moons Campaign, armed conflict ripped through South America as Koslovic, Frieden and UN forces clashed over ideological differences. Additional guerrilla attacks took place across Earth on military and nonmilitary targets, along with several concurrent off-planet skirmishes. In the later stages of the wars, Neo-Friedenists emerged as an offshoot of the Frieden movement willing to negotiate with the United Nations. Their disagreements with the mainline Frieden led to the Battle of Delambre on Luna, in which the two factions engaged one another. The Rainforest Wars also sparked additional conflicts off-planet, such as the Mars Campaign three months later. The conflict brought a great deal of suffering to the people of Earth, and caused an enormous famine.
The wars inspired some of the 22nd century's most famous literature. A Soldier's Tale: Rainforest Wars was written about this event by Jeremiah Mendez, and was considered a military classic in the 26th century. This book is a favorite of CPO Franklin Mendez.
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