Hungary–Romania relations
During World War II, Hungary and Romania became allies and participated in the war against the Soviet Union. But after the coup on 23 August 1944 Romania switched sides and fought against Hungary. Consequently, Soviet and Romanian troops invaded Hungary, occupied Northern Transylvania by October 1944 and re-established the Romanian administration in the region in March 1945. The 1947 Treaty of Paris reaffirmed the borders between Romania and Hungary as originally defined in Treaty of Trianon 27 years earlier, thus confirming the return of Northern Transylvania to Romania.
Romanian Navy during World War I
In early November, Russian-Romanian forces in Dobruja started a general offensive to recapture land lost to the Central Powers during the Second Battle of Cobadin. The Romanian Navy contributed to the offensive, with the monitor "Catargiu" landing 50 marines to occupy the town of Hârșova on 8 November, after it was abandoned by the retreating enemy. On 10 November, supporting the continuing Allied advance, two Romanian river torpedo boats landed troops at Topalu to occupy the village. On 3 December, the Romanian river torpedo boat "Căpitan Valter Mărăcineanu" was sunk on the Danube by an Austro-Hungarian mine with 1 sailor killed. On 8 December, the Navy joined the ground troops as they started retreating towards the Danube Delta, stopping near Măcin. The Romanian warships spent the last days of 1916 covering the Russians as they retreated North into Russia.