Danzig

18 March-27 May, 1807

Following the tremendous slaughter at Eylau, Napoleon Bonaparte needed to secure naval supply lines and his rear and so ordered Marshal Francois Lefebvre to deal with the formidable fortress at the Prussian port of Danzig.

With around 18,000 men of X Corps, together with specialist siege units, Lefebvre found himself facing some 16,000 defenders - almost twice as many as believed - who were well entrenched inside the well-stocked city.

The difficult terrain did not assist his cause, with swamps, canals, a lake and streams making progress slow.

There was also the danger of enemy reinforcements arriving but, by early March, Lefebvre had occupied ridges overlooking Danzig's defences.

Bridges were erected and despite the annoyances of minor sorties by the Prussians, the French were inexorably moving towards being able to assault the fortress.

On 10 May, however, a British and Russian naval force landed some 8000 Russian troops under Marshal Alexander Kamenskoi to help the defenders. As it turned out, their arrival was of limited assistance because they found the French had occupied the strategic Holm Island and were forced to fortify their own camp first.

A request to Marshal Jean Lannes quickly brought another 15,000 French troops to the scene and they succeeded in defeating Kamenskoi. Within two weeks his force had abandonned the operation and reembarked.

A final sortie did manage to buy some time for the defenders, but with his last hope for assistance gone, and the French readying for an assault, the Prussian commander, General Count von Kalkreuth, decided to ask for terms.

His approach was welcomed by Lefebvre and Bonaparte consented to the Prussians, who had agreed to end the defence before a breach in the walls had been made, being allowed to withdraw with full military honours.

The 55-day investment of Danzig was one of the few major sieges to take place in continental Europe outside of the Peninsula.