The Trent affair and Maximillian's adventure may have brought Britain and France close to involvement in the American Civil War on the side of the Confederacy, but the European power with the closest involvement in the struggle was Imperial Russia, and they were on the Union side.
As I mentioned in a previous blog, Admiral Lessovsky's squadron in New York and Washington served as a deterrent to British intervention, whilst Admiral Popov in San Francisco actually ordered his ships to fire on any ships hostile to the US if they entered the harbour. But another aspect of this cooperation was what we would now call "technology transfer". The Russians were very impressed by the performance of the ironclad Monitor at the Battle of Hampton Roads - bent on challenging the pre-eminant naval power of the time, Britain, this seemed to be just what they needed.
As Rear Admiral Butakov said in May 1862, this struck a blow at countries like "England, that slumber under the protection of the wooden walls of their ships, and only built their nations' few iron vessels as goodies to pamper their children. Now, the question of timber ships is finally resolved in all but the most stupid and improvident minds".
Lessovsky was joined in Washington by a naval architect, Artseulov, and together they discussed designs with John Ericsson, the designer of the Monitor. They decided on the slightly larger Passaic class, which also differed in having the pilot house above the turret, giving a far wider field of vision, and by March 1863 the plans were in St Petersburg. Even before the plans had arrived, the Russian Admiralty had approved the construction of ten Passaic monitors, the Uragan class.
The only real difference between the Uragans and Passaics was in armament. The Passaics used 1 x 15 inch Dahlgren smoothbore cannon and 1 x 11 inch. The Russians set up a factory to make 15 inch Dahlgens, again using plans from the US, but initially they used 9 inch Krupp guns bought from Germany. When the Dalhgen guns came on line they were used, and then in 1873 new 9 inch rifled guns were exchanged and used until the Uragans were scrapped.
The Uragans were not really ocean going boats, although they could navigate in the Baltic, the plan was to use then for coastal defence. In other words, to prevent the Royal Navy descending on St Petersburg and other Russian cities in retaliation for Russian land operations elsewhere. Nor were they especially fast, with a 160 horsepower engine capable of giving about 9 knots, according to the Austrian military journal of 1865*, but they were manoeuvrable, turning 360 degrees in about 4 1/2 minutes. They were also remarkably stable in calm waters and in a drill the Koldun ("Sorcerer") could weigh anchor, load and fire her guns in under 10 minutes.
There were other monitor types, the Admiral Lazarev class, (Spiridov, Cicagov, Greig and Lazarev) and Admiral Rusalka class (Carodjelka and Rusalka), but the Uragans were by far the most numerous. And successful in their mission. They were kept in service for over 30 years , and during that time they didn't once have to fire their guns in defence of St Petersburg.
* Österreichische militärische Zeitschrift 1865