[3] For this stubborn defense, he was promoted to colonel, and Frederick the Great awarded him the Pour le Mérite.

[1] On 26 August 1760, during the second siege of Kolberg, a united force of Swedish and Russian troops surrounded the fortress on water and land.

On 27 August, Kolberg was bombarded from the sea by the entire Russian Baltic fleet: twenty-one ships of the line, three frigates and three bomb vessels.

[5] He defended Kolberg with his limited number of troops until 18 September, when General Paul von Werner arrived with 3,800 men after a 13-day, 340 kilometres (210 mi) forced march from Silesia.

After the second siege of Kolberg, Frederick reevaluated his previously lukewarm opinion of Heyde: I am not infallible; in this man I have been greatly wrong.

[1] Financially, Heyde's heroism did not pay off; he received as a commander a salary of 600 taler against of which, shortly before his death, 800 were still owed.

Friedrich Eugen, Duke of Württemberg marched from the Swedish front in Mecklenburg and secured the surrounding countryside, but he, like the troops stranded inside the fortress, struggled with supply problems.

Rumyantsev altered his strategy: instead of wasting troops in storming entrenched defenses, he would cut off Kolberg's supplies.

In November, Württemberg abandoned Kolberg, broke through the Russian lines to reunite with Platen; their joint forces assaulted Rumyantsev unsuccessfully from the rear.

After this last effort, Platen departed as ordered by Friedrich; Württemberg tried several more times to force his way back into the fortress.