Tirpitz passed the examination for acceptance as a naval cadet on 1 April 1865 in Berlin (Crew 65) and entered the Prussian Navy on 24 June 1869. On 22 September 1869 he was promoted to Leutnant zur See. Between 1877 and 1889 he was prominently involved in the building up of the Torpedo Arm, and although on the Admiralty staff was also a member of the Torpedo Experimental Commission. During this period he commanded the yacht/torpedo ship Zieten and from 1877 to 1885 was Executive Officer and subsequently commander of the flush-decked corvette Blücher (which doubled as a torpedo experimental vessel).

On 17 September 1881 Tirpitz was promoted to Korvettenkapitän and from January 1885 to March 1886 he was head of the Admiralty's torpedo section. From April 1886 to April 1889 he was First Inspector of torpedo gunnery, and from 1885 to 1887 he was also Commander of the Torpedo-Boat Flotilla. On 24 November 1888 he was promoted to Kapitän zur See. He commanded the armoured ships Preussen from April 1889 to May 1890 and Württemberg from May to September 1890.

From January 1891 to January 1892 he was Chief of Staff at the Naval Station, Baltic, and during this period, as Chief of Staff of the Autumn Fleet Exercise, with the assistance of the commanding admiral, Freiherr von der Goltz, he enunciated the principles of Fleet tactics and deployment, later known as Service Booklet IX. On 13 May 1895 he was promoted to Konteradmiral and in March 1897 he became Secretary of State at the Office of the Reichsmarine, where he remained until March 1916.

On 28 March 1898 Tirpitz was appointed a Prussian Minister of State and on 5 December 1899 he was promoted to Vizeadmiral. On 12 June 1903 he was promoted to Admiral and on 27 January 1907 was awarded the Order of the Black Eagle (Schwarzenadlerorden). Promotion to Grossadmiral followed on 27 November 1911, and on 10 August 1915 he was awarded the Pour le Mérite. He resigned on 15 March 1916 in protest at the undertaking by the German Government not to engage in unrestricted submarine warfare.

The German Navy at the outbreak of the First World War represented the lifetime's work of Alfred von Tirpitz. It was his conviction, shared by his contemporaries (a fact which should not be overlooked by modem critics), that the new and expanding, technologically and economically flourishing German Reich required a large Fleet. This belief was also held by the Kaiser.

The case was made that Germany's acquisition of colonies (which Bismarck had renounced) created the need for overseas naval bases, which would serve the twofold purpose of protecting the colonies and enabling the navy to "show the flag" around the world   principles in line with the imperial aspirations of both the Kaiser and Tirpitz. While both of them naturally appreciated that the dream of building a war fleet greater in size than that of Great Britain was not feasible, it became the policy to build a Fleet sufficiently powerful as to represent a substantial risk for Great Britain should the latter embark upon armed conflict with Germany. Tirpitz's "Risk Theory" led to the German High Seas Fleet later being referred to by historians as the "Risikoflotte". The idea that Britain might view this German Fleet as something of a menace does not appear to have occurred to Berlin.

Contrary to what the Germans had anticipated, however, Britain's entry into the Great War on the side of Germany's enemies demonstrated that the British would indeed take the risk, as they proved again at Jutland on 31 May/1 June 1916. Despite the German tactical successes resulting from outstanding training programmes, this battle was not the German victory it was proclaimed to be, for the British won the operational and strategic aspects of it. The German High Seas Fleet had not succeeded in modifying any of the geographical disadvantages under which it was obliged to operate (the "Wet Triangle"), and would, from now on, skulk in port, outwardly quiet but inwardly simmering towards the revolt out of which the revolution would come. Tirpitz had not advocated this policy: he had always wanted to "strike with the Fleet". But the Kaiser would not have it, and before Jutland Tirpitz knew he had to go.

For their part, the British steered clear of the "Wet Triangle" and blockaded Germany instead. Final victory was theirs. Over a short period of time, Tirpitz had created, within limits, a usable weapon: any blame that the full political preconditions for its deployment had not been met fell less on Tirpitz than on the shoulders of the Kaiser, who had, ultimately, the total political responsibility.

In the Second World War, the false assessment of Britain's response and the daydream of a fleet that was far beyond Germany's capabilities to build (the famous Z-Fleet of the Wehrmacht), with the ultimate goal of becoming a world naval power, were errors which had tragic parallels in the First World War.