Now the Russians had a partial buffer zone and a hinterland—somewhere to fall back to in the case of invasion. No one was going to attack them in force from the Arctic Sea, nor fight their way over the Urals to get to them. Their land was becoming what’s now known as Russia, and to invade it from the south or southeast you would have to have a huge army and a very long supply line, and you would have to fight your way past defensive positions.

In the 18th century, Russia, under Peter the Great—who founded the Russian Empire in 1721—and then Empress Catherine the Great, expanded the empire westward, occupying Ukraine and reaching the Carpathian Mountains. It took over most of what we now know as Lithuania, Latvia, and Estonia—from which it could defend against attacks from the Baltic Sea. Now there was a huge ring around Moscow; starting at the Arctic, it came down through the Baltic region, across Ukraine, to the Carpathians, the Black Sea, the Caucasus, and the Caspian, swinging back around to the Urals, which stretched up to the Arctic Circle.

At the end of World War II in 1945, the Russians occupied territory conquered from Germany in Central and Eastern Europe, some of which then became part of the U.S.S.R., as it began to resemble the old Russian Empire writ large. This time, though, it wasn’t the Mongols at the gates; after 1949, it was NATO. The fall of the U.S.S.R. in 1991 caused Russian territory to shrink again, with its European borders ending at Estonia, Latvia, Belarus, Ukraine, Georgia, and Azerbaijan, even while NATO crept steadily closer as it incorporated more countries in Eastern Europe.

Russia’s Changing Borders

Reuters

Two of Russia’s chief preoccupations—its vulnerability on land and its lack of access to warm-water ports—came together in Ukraine in 2014. As long as a pro-Russian government held sway in the Ukrainian capital of Kiev, Russia could be confident that its buffer zone would remain intact and guard the European Plain. Even a neutral Ukraine, which would promise not to join the European Union or NATO and would uphold the lease Russia had on the warm-water port at Sevastopol in Crimea, would be acceptable. But when protests in Ukraine brought down the pro-Russia government of Viktor Yanukovych and a new, more pro-Western government came to power, Putin had a choice. He could have respected the territorial integrity of Ukraine, or he could have done what Russian leaders have done for centuries with the bad geographic cards they were dealt. He chose his own kind of attack as defense, annexing Crimea to ensure Russia’s access to its only proper warm-water port, and moving to prevent NATO from creeping even closer to Russia’s border.

The Ukraine Buffer

Reuters

The same geographic preoccupations are visible now in Russia’s intervention in Syria on behalf of Putin’s ally, Bashar al-Assad. The Russians have a naval base in the port city of Tartus on Syria’s Mediterranean coast. If Assad falls, Syria’s new rulers may kick them out. Putin clearly believes the risk of confronting NATO members in another geographic sphere is worth it.

Russia has not finished with Ukraine yet, nor Syria. From the Grand Principality of Moscow, through Peter the Great, Stalin, and now Putin, each Russian leader has been confronted by the same problems. It doesn’t matter if the ideology of those in control is czarist, communist, or crony capitalist—the ports still freeze, and the European Plain is still flat.

This article has been adapted from Tim Marshall's new book, Prisoners of Geography: Ten Maps That Explain Everything About the World.

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