River monitors are military craft designed to patrol rivers. They are normally the largest of all riverine warships in river flotillas, and mount the heaviest weapons. The name originated from the US Navy's USS Monitor, which made her first appearance in the American Civil War, and being distinguished by the use of revolving gun turrets, which were particularly useful in rivers, whose narrow channels could severely limit the directions vessels could face.
The Chapayev class were a group of cruisers built for the Soviet Navy during and after World War II. Seventeen ships were planned in total, but only seven were actually started before the German invasion. Two incomplete ships were destroyed when their building yard in Nikolaev was captured by Nazi Germany and the remaining five cruisers were completed only in 1950, with the last ship serving until 1981.
The Beograd class of destroyers consisted of three ships built for the Yugoslav Royal Navy in the late 1930s, a variant of the French Bourrasque class. Beograd was constructed in France and Zagreb and Ljubljana were built in the Kingdom of Yugoslavia. In January 1940, Ljubljana struck a reef off the port of Šibenik, and was still under repair when the German-led Axis invasion of Yugoslavia commenced in April 1941. During the invasion, Zagreb was scuttled to prevent its capture, and the other two ships were captured by the Italians. The Royal Italian Navy operated Beograd and Ljubljana as convoy escorts between Italy, the Aegean Sea, and North Africa, under the names Sebenico and Lubiana respectively. Lubiana was lost in the Gulf of Tunis in April 1943; Sebenico was seized by the Germans in September 1943 after the Italian surrender and was subsequently operated by the German Navy as TA43. There are conflicting reports about the fate of TA43, but it was lost in the final weeks of the war.
T3 was a sea-going torpedo boat that was operated by the Royal Yugoslav Navy between 1921 and 1941. Originally 78 T, a 250t-class torpedo boat of the Austro-Hungarian Navy built in 1914, she was armed with two 66 mm (2.6 in) guns, four 450 mm (17.7 in) torpedo tubes, and could carry 10–12 naval mines. She saw active service during World War I, performing convoy, escort and minesweeping tasks, anti-submarine operations and shore bombardment missions. In 1917 the suffixes of all Austro-Hungarian torpedo boats were removed, and thereafter she was referred to as 78. She was part of the escort force for the Austro-Hungarian dreadnought Szent István during the action that resulted in the sinking of that ship by Italian torpedo boats in June 1918.
The Royal Navy, commonly the Royal Yugoslav Navy, was the naval warfare service branch of the Kingdom of Yugoslavia. It was brought into existence in 1921, and initially consisted of a few former Austro-Hungarian Navy vessels surrendered at the conclusion of World War I and transferred to the new nation state under the terms of the Treaty of Saint-Germain-en-Laye. The only modern sea-going warships transferred to the new state were twelve steam-powered torpedo boats, although it did receive four capable river monitors for use on the Danube and other large rivers. Significant new acquisitions began in 1926 with a former German light cruiser, followed by the commissioning of two motor torpedo boats (MTBs) and a small submarine flotilla over the next few years. When the name of the state was changed to Yugoslavia in 1929, the name of its navy was changed to reflect this. In the late 1920s, several of the original vessels were discarded.
The Yugoslav order of battle before the invasion of Yugoslavia includes a listing of all operational formations of the Royal Yugoslav Army, Royal Yugoslav Army Air Force and Royal Yugoslav Navy immediately prior to the World War II invasion of that country in April 1941.
The Yugoslav monitor Drava was a river monitor operated by the Royal Yugoslav Navy between 1921 and 1941. She was originally built for the Austro-Hungarian Navy as the name ship of the Enns-class river monitors. As SMS Enns, she was part of the Danube Flotilla during World War I, and fought against the Serbian and Romanian armies from Belgrade to the lower Danube. In October 1915, she was covering an amphibious assault on Belgrade when she was holed below the waterline by a direct hit, and had to be towed to Budapest for repairs. After brief service with the Hungarian People's Republic at the end of the war, she was transferred to the newly created Kingdom of Serbs, Croats and Slovenes, and renamed Drava. She remained in service throughout the interwar period, but was not always in full commission due to budget restrictions.
The Yugoslav monitor Sava is a Temes-class river monitor that was built for the Austro-Hungarian Navy as SMS Bodrog. She fired the first shots of World War I just after 01:00 on 29 July 1914, when she and two other monitors shelled Serbian defences near Belgrade. She was part of the Danube Flotilla, and fought the Serbian and Romanian armies from Belgrade to the mouth of the Danube. In the closing stages of the war, she was the last monitor to withdraw towards Budapest, but was captured by the Serbs when she grounded on a sandbank downstream from Belgrade. After the war, she was transferred to the newly created Kingdom of Serbs, Croats and Slovenes, and renamed Sava. She remained in service throughout the interwar period, although budget restrictions meant she was not always in full commission.
Vardar was a Sava-class river monitor built for the Austro-Hungarian Navy as SMS Bosna, but was renamed SMS Temes (II) before she went into service. During World War I, she was the flagship of the Danube Flotilla, and fought the Serbian Army, the Romanian Navy and Army, and the French Army. She reverted to the name Bosna in May 1917, after the original SMS Temes was raised and returned to service. After brief service with the Hungarian People's Republic at the end of the war, she was transferred to the newly created Kingdom of Serbs, Croats and Slovenes, and renamed Vardar. She remained in service throughout the interwar period, although budget restrictions meant she was not always in full commission.
SMS Körös was the name ship of the Körös-class river monitors built for the Austro-Hungarian Navy. Completed in 1892, the ship was part of the Danube Flotilla, and fought various Allied forces from Belgrade down the Danube to the Black Sea during World War I. After brief service with the Hungarian People's Republic at the end of the war, she was transferred to the newly created Kingdom of Serbs, Croats, and Slovenes, and renamed Morava. She remained in service throughout the interwar period, although budget restrictions meant she was not always in full commission.
The Sava-class river monitors were built for the Austro-Hungarian Navy during the mid-1910s. The two ships of the class were assigned to the Danube Flotilla and participated in World War I. The ships survived the war and were transferred to Romania and the newly created Kingdom of Serbs, Croats and Slovenes as reparations.
The 250t class were high-seas torpedo boats built for the Austro-Hungarian Navy between 1913 and 1916. A total of 27 boats were built by three shipbuilding companies, with the letter after the boat number indicating the manufacturer. There were small variations between manufacturers, mainly in the steam turbines used, and whether they had one or two funnels. The eight boats of the T-group, designated 74 T – 81 T, were built by Stabilimento Tecnico Triestino, located at Triest. The sixteen boats of the F-group, 82 F – 97 F, were built by Ganz-Danubius at their shipyards at Fiume and Porto Re. The three M-group boats, 98 M – 100 M, were manufactured by Cantiere Navale Triestino at Monfalcone.
SMS Kaiser Max was an ironclad warship built for the Austro-Hungarian Navy in the 1870s, the lead ship of the Kaiser Max class. The ship was purportedly the same vessel that had been laid down in 1861, and had simply been reconstructed. This was a fiction, however; the head of the Austro-Hungarian Navy could not secure funding for new ships, but reconstruction projects were uncontroversial, so he "rebuilt" the three earlier Kaiser Max-class ironclads. Only the engines and parts of the armor plate were reused in the new Kaiser Max, which was laid down in February 1874, launched in December 1875, and commissioned in October 1876. The ship's career was fairly limited, in part due to slender naval budgets that prevented much active use. She made foreign visits and took part in limited training exercises in the 1880s and 1890s. Long since obsolete, Kaiser Max was removed from service in 1904 and converted into a barracks ship. After World War I, the ship was transferred to the Royal Yugoslav Navy as a war prize and renamed Tivat. Her fate thereafter is uncertain, either being sold for scrap in 1924 or retained through 1941.
The Brătianu-class river monitors were a class of four river monitors used by the Romanian Navy. They were named Ion C. Brătianu, Lascăr Catargiu, Mihail Kogălniceanu and Alexandru Lahovari.
The Temes class was a class of originally Austro-Hungarian river monitor warships used during World War I. A notable member was Bodrog.
NMS Năluca was a torpedo boat of the Royal Romanian Navy. She was commissioned in 1920, after initially serving as Tb 82 F in the Austro-Hungarian Navy during World War I. She and six more sister ships were awarded to Romania as reparations after the war ended.
The Romanian Danube Flotilla is the oldest extant naval force on the Danube, dating since 1860, when the Romanian Navy was founded. It saw service during most of the wars involving Romania, and was the most powerful river naval force in the world during the Interwar period.
During World War I, the Black Sea Fleet of the Romanian Navy fought against the Central Powers forces of the German Empire, the Ottoman Empire and Austria-Hungary. The Romanian warships succeeded in defending the coast of the Danube Delta, corresponding to an area around the port of Sulina, while also aiding in the Delta's defense from inland Central Powers forces.
