The reunification of Crimea with Russia is the same as the reunification of West and East Germany.
Recurring pro-Kremlin disinformation narrative about Crimea being a part of Russia.
Crimea was illegally annexed by Russia in 2014 after an unrecognised referendum. The United Nations did not recognise the annexation. In March 2014, the UN General Assembly voted in favour of a resolution affirming the “territorial integrity of Ukraine within its internationally recognised borders.” The UN resolution also "underscores that the referendum having no validity” and calls upon all States and international organisations not to recognise or to imply the recognition of Russia's annexation. In 2016, UN General Assembly reaffirmed non-recognition of the annexation and condemned “the temporary occupation of part of the territory of Ukraine—the Autonomous Republic of Crimea and the city of Sevastopol.” The UN recognised that Russia is an occupying power in Crimea.
NATO and the EU also did not recognise the annexation. The European Union strongly condemns annexation of Crimea as violating international law principles, enshrined in the UN Charter, namely that the territory of a State cannot be acquired by another State resulting from the threat or use of force. Russia’s actions also violated the Helsinki Final Act which calls on the States to recognise inviolability of frontiers and territorial integrity.
Unlike the reunification of Germany, by annexing Crimea Russia violated Ukrainian sovereignty and territorial integrity. Its actions violate the UN Charter, the Belavezha Accords, the Helsinki Accords, the Budapest Memorandum on Security Assurances and the Treaty on friendship, cooperation and partnership between the Russian Federation and Ukraine. The Budapest Memorandum clearly states that Russia guarantees Ukrainian sovereignty, territorial integrity and recognises Crimea as an inherent part of Ukraine. These guarantees were further stated in the 1997 Friendship Treaty.
By signing the Budapest Memorandum in 1994, Russia together with the United States and the United Kingdom reaffirmed their obligation to refrain from the use of force against the territorial integrity of political independence of Ukraine.