The Carpathian Mountains rise in the west and the Crimean Mountains in the south, but the heartland of Ukraine—slightly larger than France—is the rich flat earth that stretches for 1,600 kilometers (1,000 miles), known as the steppe. Once called the breadbasket of the Soviet Union, Ukraine also has huge deposits of coal and iron that feed heavy industry, particularly in the Donbas (Donets Basin) and Kryvyy Rih regions.

Such natural wealth tempted conquerors. In 988 Vladimir the Great adopted Christianity—which evolved into Russian Orthodoxy—to unify the Kievan Rus, a confederation of Slavic peoples. The Mongols overran the land in the 13th century, followed by the Lithuanians in the 14th century. Poland asserted dominion in 1569. Defying their Polish masters, rebel-minded peasants—the Cossacks—gathered under warlike leaders called hetmans in the vastness of the steppe. After a revolt led by Bohdan Khmelnytsky, the Cossacks formed their own state in 1649. But in 1654—still fighting the Poles—they entered a pact with Russia, which soon exerted control.

At its greatest extent, about 1880, the Russian Empire encompassed 85 percent of present-day Ukraine; the remainder was under the influence of Austria-Hungary. After the Russian Revolution, Ukraine enjoyed brief independence. Despite Lenin's promises, however, the Red Army invaded, and by 1920 most of Ukraine was Bolshevik ruled. Joseph Stalin, fearing Ukrainian nationalism, killed the intelligentsia, and, through his policy of collectivization, engineered a famine in 1932 and 1933 that took at least five million lives. Nazi occupation scourged the country during the "Great Patriotic War." The republic lost 7.5 million people, 4 million of them civilians and 2.2 million deported to Germany as laborers. After World War II, Soviet rule prevailed.

Ukraine suffered the world's worst recorded nuclear accident. On the morning of April 26, 1986, reactor No. 4 at the Chornobyl Nuclear Power Plant, 80 miles north of Kiev, exploded, sending radioactive contaminants three miles up into the atmosphere and out over parts of Europe, Asia, and North America.

A political meltdown occurred in December 1991, when 90 percent of Ukrainians voted for independence, in effect dissolving the Soviet Union. Now Ukraine faces ongoing border disputes with Russia. The new millennium has brought economic growth, with rising industrial output and falling inflation. In 2001 the country destroyed its last Soviet-era nuclear missile silo, and in 2002 it announced plans to join NATO.