Five groups fight in J.R.R. Tolkien’s Battle of the Five Armies.
The five armies are the Dwarves, Elves, Men, Goblins, and Wolves. The battle takes place near the Lonely Mountain after Smaug’s death, when several peoples converge on the dragon’s treasure and then unite against a larger Goblin and Wolf force.
The Dwarves are led by Thorin Oakenshield, while the Elves of Mirkwood are led by King Thranduil. Men from Lake-town are represented by Bard, who has just killed Smaug. The Goblins and Wolves form the opposing force, arriving from the Misty Mountains.
The battle ends with the defeat of the Goblins, but it is costly. Thorin dies after reconciling with Bilbo, and several other major figures are killed. The phrase “five armies” refers to the five participating peoples, not five individual commanders or five separate battles.