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 Romanian Naval Forces is the principal naval branch of the Romanian Armed Forces and operates in the Black Sea and on the Danube. It traces its history back to 1860.
The Flămânda Offensive, which took place during World War I between 29 September and 5 October 1916, was an offensive across the Danube mounted by the Romanian 3rd Army supported by Romanian coastal artillery. Named after the hamlet of Flămânda, the battle represented a consistent effort by the Romanian Army to stop the Central Powers' southern offensive led by August von Mackensen. The battle ended as a tactical victory for the Central Powers.
The Royal Romanian Navy during World War I (1914–1918) was divided into two fleets and fought against the forces of the Central Powers. When Romania entered the war in August 1916, the Romanian Navy was officially divided as follows :
SMS Leitha or Lajta Monitor Museumship was the first river monitor in Europe and the oldest and also the only remaining, fully restored warship of the Austro-Hungarian Navy. Currently it is moored on the Danube in Budapest near the Hungarian Parliament Building as a museum ship.
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 Enns-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 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 Danube Delta Campaign was a series of naval engagements between the Soviet Danube Flotilla and its Romanian counterpart in late June 1941, during the first days of Operation Barbarossa.
The Škoda 7 cm guns were a family of naval guns and dual-purpose guns of the Austro-Hungarian Empire that were developed and produced for the Austro-Hungarian Navy in the years before and during World War I. These guns were actually 66 mm, but the classification system for artillery rounded up to the next highest centimeter. Following the defeat of the Central Powers in World War I and the dissolution of the Austro-Hungarian empire the ships of the Austro-Hungarian Navy were divided among the victorious allies and some guns continued to be used until World War II.
NMS Mihail Kogălniceanu was a Brătianu-class river monitor of the Romanian Navy. She saw service in both world wars, being the most successful vessel in her class of four ships. Like her three sisters, she was initially built as a river monitor, but in early 1918, she was converted to a sea-going monitor. During the Second Balkan War, she supported the Romanian crossing of the Danube into Bulgaria. During World War I, she carried out numerous bombardments against the Central Powers forces advancing along the shore of the Danube and carried out the last action of the Romanian Navy before the 11 November 1918 armistice. She later fought successfully against Bolshevik naval forces during the early months of the Russian Civil War, helping secure the Budjak region.
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.
The Bombardment of Belgrade was an attack carried out by Austria-Hungary on the Serbian capital during the night of 28–29 July 1914. It is considered the first military action of World War I.
NMS Ardeal was a Temes-class river monitor originally named SMS Temes while in Austro-Hungarian Navy service. Built in 1904, Temes was the lead ship of her class and served as flag ship of the Austro-Hungarian Danube Flotilla between 1908 and 1914. After a short service in the Yugoslav Navy, she was transferred to the Romanian Navy in 1920 and served with the Romanian Danube Flotilla in World War II until 1944 when she was taken over the Soviets. She was returned to Romania in 1951 and served as a training ship under the name M.20, later M.207, until 1959 when she was scrapped.
NMS Basarabia, originally named SMS Inn, was an Enns-class river monitor built by Ganz-Danubius in Budapest between 1913 and 1915. While in Austro-Hungarian Navy service, she struck a Romanian mine and sank in 1917. She was then refloated and repaired, being transferred to the Romanian Navy as war reparations. She continued service with Romania until 1944 when she was taken by the Soviet Union. In 1951, she was returned to Romania and continued service until 1958. She was scrapped in 1960.
Austria-Hungary 
Kingdom of Yugoslavia 
Kingdom of Romania 
Soviet Union 
