The Balkan Wars were a series of two conflicts that took place in the Balkan states in 1912 and 1913. In the First Balkan War, the four Balkan states of Greece, Serbia, Montenegro and Bulgaria declared war upon the Ottoman Empire and defeated it, in the process stripping the Ottomans of their European provinces, leaving only Eastern Thrace under the Ottoman Empire's control. In the Second Balkan War, Bulgaria fought against the other four original combatants of the first war. It also faced an attack from Romania from the north. The Ottoman Empire lost the bulk of its territory in Europe. Although not involved as a combatant, Austria-Hungary became relatively weaker as a much enlarged Serbia pushed for union of the South Slavic peoples. The war set the stage for the July crisis of 1914 and thus served as a prelude to the First World War.
The First Balkan War lasted from October 1912 to May 1913 and involved actions of the Balkan League against the Ottoman Empire. The Balkan states' combined armies overcame the initially numerically inferior and strategically disadvantaged Ottoman armies, achieving rapid success.
The Second Balkan War was a conflict that broke out when Bulgaria, dissatisfied with its share of the spoils of the First Balkan War, attacked its former allies, Serbia and Greece, on 16 (O.S.) / 29 (N.S.) June 1913. Serbian and Greek armies repulsed the Bulgarian offensive and counterattacked, entering Bulgaria. With Bulgaria also having previously engaged in territorial disputes with Romania and the bulk of Bulgarian forces engaged in the south, the prospect of an easy victory incited Romanian intervention against Bulgaria. The Ottoman Empire also took advantage of the situation to regain some lost territories from the previous war. When Romanian troops approached the capital Sofia, Bulgaria asked for an armistice, resulting in the Treaty of Bucharest, in which Bulgaria had to cede portions of its First Balkan War gains to Serbia, Greece and Romania. In the Treaty of Constantinople, it lost Adrianople to the Ottomans.
The Treaty of Bucharest was concluded on 10 August 1913, by the delegates of Bulgaria, Romania, Serbia, Montenegro and Greece. The Treaty was concluded in the aftermath of the Second Balkan War and amended the previous Treaty of London, which ended the First Balkan War. About one month later, the Bulgarians signed a separate border treaty with the Ottomans, who had regained some territory west of the Enos-Midia Line during the second war.
The Romanian War of Independence is the name used in Romanian historiography to refer to the Russo-Turkish War (1877–78), following which Romania, fighting on the Russian side, gained independence from the Ottoman Empire. On April 16 [O.S. April 4] 1877, Romania and the Russian Empire signed a treaty at Bucharest under which Russian troops were allowed to pass through Romanian territory, with the condition that Russia respected the integrity of Romania. Consequently, the mobilization of the Romanian troops also began, and about 120,000 soldiers were massed in the south of the country to defend against an eventual attack of the Ottoman forces from south of the Danube. On April 24 [O.S. April 12] 1877, Russia declared war on the Ottoman Empire and its troops entered Romania through the newly built Eiffel Bridge, on their way to the Ottoman Empire. Due to great losses, the Russian Empire asked Romania to intervene. On July 24 [O.S. July 12] 1877, the first Romanian Army units crossed the Danube and joined forces with the Russian Army.
The Kingdom of Bulgaria participated in World War I on the side of the Central Powers from 14 October 1915, when the country declared war on Serbia, until 30 September 1918, when the Armistice of Salonica came into effect.
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 :
The participation of Greece in the Balkan Wars of 1912–1913 is one of the most important episodes in modern Greek history, as it allowed the Greek state to almost double its size and achieve most of its present territorial size. It also served as a catalyst of political developments, as it brought to prominence two personalities, whose relationship would dominate the next decade and have long-lasting repercussions for Greece: the Prime Minister Eleftherios Venizelos, and the Army's commander-in-chief, the Crown Prince and later King, Constantine I.
NMS Elisabeta was a small protected cruiser built for the Romanian Navy during the 1880s by Armstrong in Britain as Romania lacked the ability to build the ship itself. Serving mainly as a training ship, she represented Romania at the opening of the Kiel Canal in 1895. She helped protect Romanian interests in Constantinople during the First Balkan War in 1912–1913, but played no significant part in the Second Balkan War and was partially disarmed during World War I. Employed as a barracks ship after the war, the ship was scrapped in 1926.
The Bulgarian Third Army was a Bulgarian field army during the Balkan Wars, World War I, and World War II.
NMS Amiral Murgescu was a minelayer and convoy escort of the Romanian Navy, the first sea-going warship built in Romania and the largest Romanian-built warship of World War II. She laid numerous minefields, from the Bulgarian port of Burgas to the Crimean port of Sevastopol, which inflicted significant losses to the Soviet Black Sea Fleet. She also carried out numerous convoy escort missions and took part in the Axis evacuation of the Crimea in May 1944. Due to her success in combat, she was decorated twice by May 1944. She was captured by the Soviet Union in September 1944 and served until 1988, when she was scrapped.
NMS Grivița was a gunboat of the Romanian Navy, built in 1880. It was the first warship acquired by the Kingdom of Romania after gaining independence in 1878 and the first military ship of the Romanian Black Sea Fleet. Throughout her career, she saw service on both the Black Sea and the Danube during the Second Balkan War and the First World War.
The Romanian Navy during World War II was the main Axis naval force in the Black Sea campaigns and fought against the Soviet Union's Black Sea Fleet from 1941 to 1944. Operations consisted mainly of mine warfare, but there were also escort missions and localized naval engagements. The largest naval action fought by the Romanian Navy was the 26 June 1941 Raid on Constanța, and its most extensive operation was the 1944 evacuation of the Crimea.
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. During the interwar period, she contributed to the suppression of the Tatarbunary Uprising and was rearmed with longer main guns towards the end of the 1930s. During World War II, she fought several engagements against the Soviet Navy in the first month of the Eastern Front, but was ultimately sunk by Soviet aircraft shortly after Romania ceased hostilities against the Soviet Union, on 24 August 1944.
NMS Rândunica was the first torpedo boat of the Romanian Navy. A small British-built spar torpedo boat, she was commissioned in 1875 and fought during the Romanian War of Independence and during World War I.
The action of 26 June 1941 consisted in an engagement between the navies of the Soviet Union and the Kingdom of Romania, taking place on the Chilia branch of the Danube Delta, near the commune of Ceatalchioi. The action resulted in a Romanian victory and the withdrawal of the Soviet vessels, one of them being damaged and later captured.
The second Romanian campaign of World War I was one of the shortest military operations of the war, taking place during the last two days of the war, 10 and 11 November 1918. With no significant battles, it yielded important territorial as well as material gains for the Romanians, and was a prelude to the Hungarian–Romanian War, which would start two days later, on 13 November.
The Raid on Ruse was the first naval action to take place on the Romanian front during World War I. It took place on the first day of the campaign, 27 August 1916, just as Romanian troops were crossing the border into Transylvania, then part of Austria-Hungary.
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.
NMS Alexandru cel Bun was the first minelayer of the Romanian Naval Forces. Built by the United Kingdom in 1882, she served in the Romanian Navy for five decades, until being scrapped in the mid-1930s.
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