[1] The Swedish besiegers, being led by Carl Gustaf Wrangel, successfully made the Danish commander surrender after spreading rumours that Copenhagen had fallen to the Swedes and convincing him that continued resistance was futile.

On 16 August, during the Siege of Copenhagen, King Charles X Gustav sent his most trusted man, Carl Gustaf Wrangel, to besiege Kronborg which was situated at the Øresund, referred to as "the Sound" in English.[2][which?]

When Carl Gustaf Wrangels and his army of 3,000 men[3] marched into Helsingør on the evening of 16 August, they were quickly bombarded with 24 and 36 pound cannonballs from the garrison in Kronborg.

[5] However, Kronborg was built with solid granite and had a double defensive ring, with the inner one having four bastions and a moat, also being stocked with large amounts of provisions, ammunition, and artillery, of which there were over 90 guns.

The Danes had also established a battery of falconets and hook guns on the square roof of the tower, which they could use to fire directly onto the Swedes who ran around to seek shelter in the surrounding buildings.

Erik Dahlbergh led the construction of the Swedish batteries, while he also held responsibility for the siege works at Copenhagen.

In the early autumn, storms began sweeping in from the North Sea, drenching both the Swedes and Danes in rain, filling trenches and graves with water.

Spreading rumours that Copenhagen had fallen, Wrantel managed to convince Beenfeldt, the Danish commander, that the battle was already lost.

When the storm bridge was brought down and the Danes came out, Dahlbergh was there, waiting with a few hundred men to quickly take control of Kronborg.

The gate to the Sound was now effectively blocked, and Wrangel's forces were able to march back towards Copenhagen with heavy cannons, a welcome reinforcement for the main Swedish army which had rather weak artillery.