Forum Copenhagen was designed by Oscar Gundlach-Pedersen, and the lighting was from Poul Henningsen's brand new PH-lamp.

During World War II, the Danish resistance movement group Holger Danske destroyed the original hall in an act of sabotage in August 1943.

An annual six-day bicycle race was originally held here and was later moved to Ballerup Super Arena.

In 1997, the Forum concluded an extensive renovation of the roof costing 70 million DKK, resulting in better acoustic sound and more concerts.

On 22nd–24th of July 2022, the arena plays host for the playoff games of the 2022 Valorant Champions Tour: Stage 2 Masters, in which it hosts the Semifinals and the Grand Finals with live audience, making it the first international Valorant Esports event to be held with live audience.