Battle of Heligoland (1864)

The Battle of Heligoland (or Helgoland) was fought on 9 May 1864, during the Second War of Schleswig between the navy of Denmark and the allied navies of Austria and Prussia south of the then-British North Sea island of Heligoland where the Battle of Heligoland (1849) had taken place.

When the Danish forces had caused the flagship of the Austrian commander, Freiherr von Tegetthoff, to burst into flames, he withdrew his squadron to neutral waters around Heligoland. It was the last significant naval battle fought by squadrons of wooden ships and also the last one involving Denmark.

Although the battle ended with a tactical victory for Denmark, it had no impact on the outcome of the war. A general armistice came into effect on 12 May, and Denmark had lost the war.

The battle
As the Danish squadron approached from the north, it sighted the British frigate Aurora at about 10 a.m. and soon afterwards five more ships to the Southwest. The two squadrons approached each other, and Schwarzenberg opened fire at 13.15 p.m. The Danes closed and returned fire when the distance had much shortened. When Tegetthoff altered course to the West in an effort to "cross the T", Suenson turned to port. With the Prussian gunboats unable to keep pace and far behind, the Austrian and Danish squadrons passed each other at a distance of about 1 nmi, exchanging furious fire. Tegetthoff turned about so as to prevent the gunboats being cut off, and both flotillas then sailed on a parallel course southwest, continuing to battle each other. Niels Juel duelled Schwarzenberg, while Jylland and Hejmdal concentrated on Radetzky. The Prussian gunboats were too far away to play a role.

At about 15.30 p.m., Schwarzenberg caught fire and was unable to continue. Tegetthoff broke off the encounter and took his ships into the neutral waters near Heligoland. Aurora had observed the action and stood ready to protect the neutrality of the British Heligoland waters, so that Suenson had to abandon his pursuit at about 16.30 p.m.

Aftermath
Suenson waited outside the British zone of 3 nmi, but the Austrian-Prussian squadron was able to escape during the night to Cuxhaven at the mouth of the Elbe. With the armistice set to come into effect on 12 May, Suenson was ordered back to Copenhagen, thus ending the naval blockade.

In Denmark as in Austria, the outcome of the battle was regarded as a victory. The Danish squadron was enthusiastically welcomed in Copenhagen, while in Austria, Tegetthoff was awarded with his promotion to rear admiral. He subsequently led the reform of the Austrian naval establishment.

The frigate Jylland is today located in a drydock in a maritime museum in Ebeltoft, Denmark.

Order of battle
Denmark (Captain Edouard Suenson)
 * Niels Juel 42-gun screw frigate, crew 422
 * Jylland, 44-gun screw frigate, crew 327
 * Hejmdal 16-gun screw corvette, crew 260

Austria (Captain Wilhelm Freiherr von Tegetthoff)
 * Schwarzenberg, 51-gun screw frigate, crew 498
 * Radetzky 37-gun screw frigate, crew 372

Prussia
 * Preussischer Adler, 4-gun paddle steamer, crew 110
 * Blitz, 3-gun 350-ton gunboat, crew 66
 * Basilisk, 3-gun 350-ton gunboat, crew 66

Memorials
There is a memorial commemorating fallen Austrian sailors and marines from the battle, in a park in Altona, Hamburg, Germany.

In Copenhagen, at Nyboder, there is a monument conmemorating Edouard Suenson who led the Danish forces in the battle.