Credit…Denis Sinyakov for The New York Times

KYIV, Ukraine – The Crimean Peninsula hangs like a diamond off the southern coast of Ukraine, blessed with a temperate climate, vast beaches, lush wheat fields and orchards full of cherries and peaches.

It is also a critical gathering place for Russia’s invasion of Ukraine.

Connected by a bridge to Russia and serving as home to Moscow’s Black Sea Fleet, Crimea is a vital link in the supply chain of the Russian military supporting tens of thousands of troops who now occupy a vast part of southern Ukraine.

For President Vladimir V. Putin, it is sacred land, having been declared part of Russia by Catherine the Great in 1783, helping pave the way for his empire to become a naval power. Soviet leader Nikita S. Khrushchev gave it to Ukraine in 1954. And because Ukraine was then a Soviet republic, that didn’t change much.

But when the Soviet Union collapsed nearly four decades later, Russia lost its gem. Mr. Putin thus claimed to right a historic wrong by illegally annexing Crimea in 2014.

Credit…Tyler Hicks/The New York Times

Mr Putin promised at the time that he had no intention of further dividing Ukraine. Yet eight years later, in February, tens of thousands of Russian troops stormed the northern peninsula, sparking the current war.

In recent days, military targets in Crimea have been attacked and the peninsula once again finds itself in the midst of a major power struggle.

Military significance

At the start of the war, Russian troops from Crimea seized large swaths of the Kherson and Zaporizhia regions which remain key to the Russian occupation of southern Ukraine.

Crimea, in turn, offers key logistical support to Russia to maintain its occupying army, including two main rail links that Russia relies on to move heavy military equipment. Crimean airbases were used to stage sorties against Ukrainian positions, and the peninsula provided a launching ground for Russian long-range missiles.

The peninsula is also home to Russia’s Black Sea Fleet, helping Russia maintain its dominance over the sea, including a naval blockade that crippled Ukraine’s economy.

A place in the sun

Russia is cold – a fifth of the country is above the Arctic Circle. But it can be positively mild in the sun-drenched Crimean city of Yalta.

“Russia needs her paradise,” wrote Prince Grigory Potemkin, general and lover of Catherine the Great, when he urged her to claim the land.

Crimea is where Tsars and Politburo presidents kept vacation homes. Before the West imposed sanctions on Russia for illegally annexing the peninsula, it was a place where wealthy Eastern Europeans went to relax and party.

“Casinos buzz and ping all over the city’s pine-lined lanes,” proclaimed a New York Times Travel article about Yalta in 2006, adding, “Much — if not everything — happens in this booming seaside town .”

Tourism fell sharply after 2014. But when explosions erupted at an airbase last week near Crimea’s west coast, there were still visitors to nearby resorts taking photos and videos as the black smoke hid the sun.

Credit…Reuters

Links with Russia

“Crimea has always been an integral part of Russia in people’s hearts and minds,” Putin said in his 2014 speech marking the annexation. But this is a selective reading of history.

Over the centuries, Greeks and Romans, Goths and Huns, Mongols and Tatars have all claimed the land.

And perhaps no group in Crimea watched the unfolding war with as much concern as the Tatars, Turkish Muslims who migrated from the Eurasian steppes in the 13th century.

They were brutally targeted by Stalin, who – in a foreshadowing of the Kremlin’s justification for its current war – accused them of being Nazi collaborators and deported them en masse. Thousands of people died in the process.

In 1989, Mikhail Gorbachev, the last Soviet leader, allowed the Tatars to return to Crimea. And before the 2014 annexation, they made up about 12% of Crimea’s population, or about 260,000 people.

In 2017, Human Rights Watch accused Moscow of intensifying the persecution of the Tatar minority in Crimea, “with the apparent aim of completely silencing dissent on the peninsula”.