The Romanian War of Independence (Romanian: Războiul de Independență al României) is the name used in Romanian historiography to refer to the phase of the Russo-Turkish War (1877–78), in which Romania, fighting on the Russian side of the war, 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 around 114,000 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.

After the declaration of war by Russia in 1877, Grand Duke Nikolai Nikolaevich announced his intention of entering Romanian territory. The Romanian parliament announced a special sitting of the chamber on April, 26 to address the issue and the possibility of joining the war and under what terms.

On May 21 [O.S. May 9] 1877, in the Romanian parliament, Mihail Kogălniceanu read the act of independence of Romania as the will of the Romanian people. A day later, on May 22 [O.S. May 10] 1877, the act was signed by Prince Carol I. For symbolic reasons, the date of May 10 was celebrated as Independence Day, until 1947, since it also marked the celebration of the day when the German Prince Carol first came to Bucharest (May 10, 1866). On May 11 a resolution was adopted by the chamber authorizing the Government to use every possible endeavour to obtain the recognition of Romanian independence at the end of the war. After the Declaration, the Romanian government immediately cancelled paying tribute to the Ottoman Empire (914,000 lei), and the sum was given instead to the Romanian War Ministry.

Prince Carol I accepted the Duke's proposal to become the Marshal of the Russian troops in addition to the command of his own Romanian army, thus being able to lead the combined armed forces in the conquest of Plevna. The Romanian Army was divided into the first Army Corps under Colonel Lupu and Second Army Corps under Colonel Radovici. With his army's success in the Grivitsa and Rahova, the Plevna citadel capitulated on 28 November 1877, and Turkish General Osman Pasha surrendered the city, along with his garrison and sword to the Romanian colonel Mihail Cerchez and Russian division commander Ivan Ganetsky. After the occupation of Plevna, the Romanian Army would return to the Danube and succeed in battles in Vidin and Smârdan.

On 19 January 1878, the Ottoman Empire requested an armistice, which was accepted by Russia and Romania. Romania won the war but at a cost of about 10,000 casualties. Additionally, another 19,084 soldiers fell sick during the campaign. Its independence from the Porte was finally recognized on 13 July 1878.

The Romanian Navy consisted of three gunboats: Ştefan cel Mare, România and Fulgerul and one spar torpedo boat, Rândunica. The three gunboats displaced 352, 130 and 85 tons respectively. Ştefan cel Mare and România were each armed with four guns and Fulgerul with one gun. Despite its inferiority on paper, the Romanian Navy destroyed many Turkish river gunboats.

According to the Russian-Romanian treaty signed in April that year, the Romanian spar torpedo boat Rândunica served under joint Romanian-Russian command. She was also known as Tsarevich by the Russians. Her crew consisted of two Russian Lieutenants, Dubasov and Shestakov, and three Romanians: Major Murgescu (the official liaison officer with the Russian headquarters), an engine mechanic and a navigator. The attack of Rândunica took place during the night of 25–26 May 1877, near Măcin. As she was approaching the Ottoman monitor Seyfi, the latter fired three rounds at her without any effect. Before she could fire the fourth round, Rândunica's spar struck her between the midships and the stern. A powerful explosion followed, with debris from the Ottoman warship rising up to 40 meters in the air. The half-sunk monitor then re-opened fire, but was struck once again, with the same devastating effects. The crew of Seyfi subsequently fired their rifles at Rândunica, as the latter was retreating and their monitor was sinking. Following this action, Ottoman warships throughout the remainder of the war would always retreat upon sighting spar torpedo boats. The Russian Lieutenants Dubasov and Shestakov were decorated with the Order of St. George, while Major Murgescu was decorated with the Order of Saint Vladimir as well as the Order of the Star of Romania. Rândunica was returned to full Romanian control in 1878, after the Russian ground forces had finished crossing the Danube. The Ottoman monitor Seyfi was a 400-ton ironclad warship, with a maximum armor thickness of 76 mm and armed with two 120 mm guns.

Another Ottoman monitor, the Podgoriçe, was shelled and sunk by Romanian coastal artillery on 7 November 1877.