General-Admiral Grand Duke Konstantin Nikolayevich, a younger brother of Emperor Alexander II, directed the restoration of the fleet. In 1855, having placed the Russian Navy and Naval Department under his command, Konstantin Nikolayevich started reforms to reduce the staffs of the central administrations and coastal units. For this the Grand Duke enlisted the administrative skills of young seamen such as Andrey Popov, Ivan Shestakov, Grigory Butakov, Ivan Likhachev, Voin Rimsky-Korsakov and Stepan Lesovsky, all of whom later became celebrated admirals.
Following the Crimean War, the Baltic Fleet was rebuilt, but no more sailing ships were added. The new Baltic Fleet consisted of eighteen ships of the line and ten frigates, all steam powered and with screw propellers. To compensate for the lack of a Black Sea Fleet, it was decided that a Mediterranean squadron should be created. At the same time, in order to defend the Far East, the Siberian Flotilla and the Pacific squadron were formed. The Pacific squadron was composed of corvettes and clippers sent from the Baltic Fleet. In 1860, a post was founded at Vladivostok on the coast of Golden Horn Bay in the Harbour of Peter the Great, replacing Nikolayevsk-on-the-Amur as Russia's principal Pacific port.
The Russian squadrons familiarized themselves with the Far Eastern waters, and crews gained the invaluable experience of long voyages. The demonstration of naval strength also made life easier for Russian diplomats. Thus, in 1860-1861, Rear Admiral Likhachev's Pacific squadron of ten steam-cruisers appeared so overwhelming that, without firing a single shot, China signed the Aigun and Peking Agreements.
In 1863, Great Britain, using an insurrection in Poland as her pretext, again decided to put together an anti-Russian alliance. Russia responded by defending the Gulf of Finland and also dispatching cruisers. The Atlantic squadron of Rear Admiral Lesovsky, including the screw-frigates Alexander Nevsky, Oslyabya, Peresvet, the corvettes Vityaz and Varyag and the clipper Almaz, arrived in New York. At approximately the same time, Popov's squadron of propeller corvettes Bogatyr, Kalevala, Rynda and the clippers Abrek and Gaydamak gathered at ports on the west coast of the United States. This American "expedition" enabled the Russian fleet to achieve two objectives. Firstly, Great Britain did not continue its naval struggle with Russia because the British perceived a very real threat at sea. Second, by their presence, Russian seamen were able to support the United States in its struggle with the Confederacy.
In 1861, Russia ordered its first armoured iron ship from Great Britain. The floating armoured battery Pervenets was intended for the defence of Russia's northern capital. In two years a whole series of armoured ships were built in Saint Petersburg, including two floating armoured batteries, ten monitors and one two-turret gunboat. The construction of these larger vessels was already in progress when, between 1866 and 1871, Russia launched several turret-frigates, including the Admiral Lazarev and Admiral Spiridov, and turret-boats like the Rusalka [Mermaid]. In 1864, the first Russian sea-going armoured ship Sevastopol, with a displacement of 6,145 tons, was launched in the Finnish Gulf at Kronstadt; it was followed by the Petropavlovsk and Knyaz Pozharsky. Russia consistently proved that its shipbuilding was equal to that of any nation in the world. In 1872, under the direction of Rear Admiral Popov, Russia produced the world's largest and most powerful turret battleship Pyotr Veliky [Peter the Great], with a displacement of 10,105 tons and, in 1873, the world's first armoured cruiser, the 5,300 ton frigate General-Admiral.
By the late 1870's, the military power of the Russian fleet was ranked third in the world. In 1871, Russia rejected the terms of the Paris Treaty and began rebuilding its Black Sea Fleet. Russian officers and seamen, who had gained experience during expeditions in the 1860's and 70's, returned to the Black Sea Fleet to demonstrate the success of their training and their high level of combat skills. Under the guidance of Admirals Likhachev and later Butakov, the advanced School of Marine and Tactical Training was founded for instructing the armoured squadron of the Baltic Fleet. Rear Admiral Rimsky-Korsakov reformed the Naval Cadets Corps, and in 1877 the Nikolayevsky Naval War College became Russia's leading institution for the training of officers' ranks. The abrogation, in 1863, of corporal punishment and the transition, in 1874, to compulsory seven-year military service for lower ranks also corresponded to this era of reforms.
The Artillery and Mine Training Detachments prepared highly qualified experts. Due to the efforts of Rear Admiral Konstantin Pilkin, mine laying was seriously studied as a tactical discipline. This would soon prove useful in the war against Turkey.