In 1884 Souchon, with the rank of Kapitän, had risen to command a training ship specialising in mine laying techniques.

After serving as chief of staff for the Baltic naval squadron he reached the ranks of Konteradmiral in April 1911 and Rear Admiral of the High Sea Fleet six months later.

He successfully eluded British attempts to corner him (see Pursuit of Goeben and Breslau) and on 10 August 1914, his small squadron arrived at the Dardanelles.

At the outbreak of the war, Winston Churchill caused outrage when he "requisitioned" without compensation two almost completed Turkish battleships in British shipyards, Sultan Osman I and Reshadieh, that had been financed by public subscription.

On 15 August 1914, in the aftermath of Souchon's daring dash to Constantinople, Turkey cancelled their maritime agreement with Britain and the Royal Navy mission under Admiral Limpus, and left by 15 September.

On 29 October 1914, Souchon's fleet launched the Black Sea Raid, a naval attack which brought the Ottoman Empire into World War I.

For the next three years, Souchon attempted to reform the Ottoman Navy while conducting a number of raids on Russian shipping, ports, and coastal installations in the Black Sea.

Promoted to vice admiral, Souchon was awarded the Pour le Mérite, Germany's highest military order, on 29 October 1916.

At the outbreak of the Kiel mutiny on 3 November 1918, Souchon asked for outside troops, but revoked his request for military help when his staff claimed the situation was under control.