After Ukrainian independence in 1991, most of the peninsula was reorganised as the Autonomous Republic of Crimea. The Soviet fleet in Crimea was in contention, but a 1997 treaty allowed Russia to continue basing its fleet in Sevastopol.

Crimea, autonomous republic, southern Ukraine. The republic is coterminous with the Crimean Peninsula, lying between the Black Sea and the Sea of Azov. In 2014 Russia covertly invaded and illegally annexed Crimea, a move that was denounced by the international community.

Following the dissolution of the Soviet Union, the Republic of Crimea was formed in 1992, although the republic was abolished in 1995, with the Autonomous Republic of Crimea established firmly under Ukrainian authority and Sevastopol being administered as a city with special status.

Perspective: Crimea was Putin’s trophy. Ukraine is turning it into a test of command, supply lines and political nerve.

While the takeover of Crimea was nearly bloodless, the situation in eastern Ukraine quickly descended into a state of open warfare that claimed more than 10,000 lives over the next four years.

Stay on top of Crimea latest developments on the ground with Al Jazeera’s fact-based news, exclusive video footage, photos and updated maps.

A serviceman in Russian-held Crimea opened fire on fellow soldiers and civilians, killing four people and wounding four, officials said.

Crimea seems set for more suffering, however, as Ukraine’s campaign appears to be mounting.

Breaking Russia’s military hold on Crimea has significance beyond Ukraine, disrupting Moscow’s military operations out of its Black Sea port — for example, the peninsula was the logistics hub supporting Russia’s Syria campaign from 2015 to 2024.

Here are five things to know about Crimea, a strategic area of outstanding beauty that has played a central part in the conflict between – and history of – Russia and Ukraine.