Battles of Kopperberget and Opphöga ferry

The Battles of Kopparberget and Opphöga ferry were a series confrontations between an insurgent army under Erik Karlsson Vasa and a Dalecarlian army led by Sten Sture the Elder, and Nils Sture at Kopparberget and Opphöga ferry in 1470. The battles resulted in a defeat for the insurgents.

Reason behind Erik Karlssons rebellion
The exact reason for his rebellion is unknown, with some sources stating that Erik Karlsson was thirsty for war, and began his rebellion for this reason. With others saying that it was old loyalists to Jöns Bengtsson Oxenstierna that had rose up again, and another possible reason being that Karl Knutsson had angered the nobility by forbidding them from engaging in piracy.

Beginning of the rebellion
The rebellion began on 13 October 1469, with Erik Karlsson's men marching into Vadstena and kidnapping several of Karl Knutssons advisors, however, their attempt to kidnap Karl Knutsson himself ends in failure, since he had not arrived to Vadstena in time.

Prelude
After pacifying the population around the Mälaren, Erik went against the population of Dalarna in January 1470. This would turn out to be a disaster.

Battle of Kopparberget
On January 10 after marching from Hedemora, Eriks troops were confronted by a Dalecarlian peasant vanguard army around 20 miles from Kopparberget. Erik decided that the terrain was undesirable, and likely after hearing news that the main force was close, he chose to retreat.

Battle of Opphöga ferry
On January 13, during his retreat from Kopparberget, Erik attempted to flee over the Dalälven when his force was intercepted by the main Dalecarlian force, which only consisted of around 105 men under the command of Nils Sture and his brother-in-law Hans Aagessøn Tott, during the battle, Erik suffered a crushing defeat, with the majority of his army being destroyed and 1,500 pieces of armor being taken by the army under Nils Sture and Hans.

Aftermath
As a result of the battle at Opphöga, Erik along with other leaders like Trötte Karlsson, and Herr Erik Nilsson were forced to flee to Denmark.