Unification of Moldova and Romania in the context of "Pridnestrovian Moldavian Soviet Socialist Republic"

Greater Romania (Romanian: România Mare) is the Kingdom of Romania during the interwar period, within its borders achieved after the Great Union; or the related pan-nationalist ideal of a nation state which would incorporate all Romanian-speakers.

In 1920, after the incorporation of Transylvania, Bukovina, Bessarabia and parts of Banat, Crișana, and Maramureș, the Romanian state reached its largest peacetime geographical extent (295,049 km). Today, the concept serves as a guiding principle for the unification of Moldova and Romania.

Transnistria, officially known as the Pridnestrovian Moldavian Republic (PMR) and locally as Pridnestrovie, is a landlocked breakaway state internationally recognised as part of Moldova. It controls most of the narrow strip of land between the Dniester river and the Moldova–Ukraine border, as well as some land on the other side of the river's bank. Its capital and largest city is Tiraspol. Transnistria is officially designated by the Republic of Moldova as the Administrative-Territorial Units of the Left Bank of the Dniester (Romanian: Unitățile Administrativ-Teritoriale din stînga Nistrului) or as Stînga Nistrului ("Left (Bank) of the Dniester").

The region's origins can be traced to the Moldavian Autonomous Soviet Socialist Republic (MASSR), which was formed in 1924 within the Ukrainian SSR. During World War II, the Soviet Union took parts of the MASSR, which was dissolved, and of the Kingdom of Romania's Bessarabia to form the Moldavian Soviet Socialist Republic in 1940. The present history of the region dates to 1990, during the dissolution of the Soviet Union, when the Pridnestrovian Moldavian Soviet Socialist Republic was established in hopes that it would remain within the Soviet Union should Moldova seek unification with Romania or independence, the latter occurring in August 1991. Shortly afterwards, a military conflict between the two parties started in March 1992 and concluded with a ceasefire in July that year.

Moldovans, sometimes referred to as Moldavians (Romanian: moldoveni, Moldovan Cyrillic: молдовень, pronounced [moldoˈvenʲ]), are an ethnic group native to Moldova, who mostly speak the Romanian language, also referred to locally as Moldovan. Moldovans form significant communities in Romania, Italy, Ukraine and Russia.

There is an ongoing controversy in Moldova over whether Moldovans constitute an ethnic group separate from Romanians or not. 77.18% and 7.9% of the Moldovan population declared Moldovan and Romanian ethnicity respectively in the 2024 Moldovan census, with 49.2% declaring their mother language to be Moldovan and 31.3% declaring it to be Romanian. According to opinion polls, around one third of Moldova's population supports unification with Romania.

In 2018, over a hundred localities in Moldova and dozens in Romania issued symbolic declarations of unification (Romanian: declarații de unire, sg.: declarație de unire) with the other country. Such declarations were also issued by some Moldovan districts and Romanian counties (which are respectively each country's first-level administrative divisions), members of the Moldovan and Romanian diasporas and other entities.

A movement for the unification of Moldova and Romania exists in both countries. Both share a common Romanian language, an Eastern Orthodox faith and strong cultural and historical connections. Supporters of the movement look back on the union of Bessarabia with Romania on 27 March 1918, Bessarabia being a region corresponding up to a point with modern Moldova. As the regions of Bukovina and Transylvania also united with Romania in 1918, with the three unifications being collectively known as the Great Union (Romanian: Marea Unire) among Romanians, 2018 was a symbolic year for unionists and nationalists, celebrated as the centenary of the Great Union.