He is often considered by some Austrian historians to be one of the most adept naval officers of the 19th-century, due to his tactical inventiveness, sense of command, and inspirational leadership.

This service brought him to the favorable notice of Archduke Ferdinand Maximilian of Austria, the Oberkommandant der Marine (High Commander of the Navy), with whom he had been acquainted since 1850.

[3] During the Second Schleswig War, Tegetthoff as a Kommodore was given command, in February 1864, of a small Austrian squadron that sailed to the North Sea to support the weaker Prussian naval forces against the superior Danish navy which was blockading northern German ports.

Although the action was a tactical defeat for Tegetthoff, he achieved his main objective since the Danish squadron was shortly thereafter recalled to Copenhagen, lifting the blockade of the Elbe and Weser ports.

Tegetthoff's telegraphic dispatch was answered by Emperor Franz Josef I with another on 12 May 1864 promoting him Kontreadmiral (Rear Admiral) and conferring upon him the Order of the Iron Crown.

He received congratulatory telegrams from Ferdinand Maximilian, by then the embattled Emperor of Mexico, and Vizeadmiral Hans Birch Dahlerup, former Oberkommandant der Marine (High Commandant of the Navy).

Tegetthoff was decorated with the Commander's Cross of the Military Order of Maria Theresa and made honorary citizen of Vienna.

Following the victory of Lissa, Tegetthoff urged Franz Josef to annex the hinterland of the Dalmatian coast, so as to protect the region for development of naval bases.

Upon the execution of Ferdinand Maximilian by the Mexican government of Benito Juárez, Tegetthoff was sent with the screw frigate Novara to bring his body home to Austria, arriving in the port of Trieste on 16 January 1868.

In March 1868 Tegetthoff took also charge as Chef der Marinesektion (Chief of the Naval Section) of the War Ministry of the new dual monarchy.

Ships named for Tegetthoff included: Of these, the first was used in the 1872–74 arctic expedition of Julius von Payer and Karl Weyprecht which discovered Franz Josef Land in 1873.