Donets basin

The Donbass or Donbas (Ukrainian: Донба́с) is a historical, cultural, and economic region in eastern Ukraine. The word "Donbass" is a portmanteau formed from Donets Basin (Ukrainian: Донецький басейн, translit. Donetskyj basejn; Russian: Донецкий бассейн, Donetskij bassejn), which refers to the river Donets that flows through it. Multiple definitions of the region's extent exist, but its boundaries have never been officially demarcated.

The most common definition in use today refers to the Donetsk and Luhansk regions of Ukraine, whilst the historical coal mining region excluded parts of these oblasts, and included areas in Dnipro region and Southern Russia. A Euroregion of the same name is composed of Donetsk and Luhansk oblasts in Ukraine and Rostov Oblast in Russia. Donbass formed the historical border between the Zaporizhian Sich and the Don Cossack Host. It has been an important coal mining area since the late 19th century, when it became a heavily industrialised territory.

In March 2014, following the 2014 Ukrainian revolution and Russian military intervention, large swaths of the Donbass became gripped by unrest. This unrest later grew into a war between pro-Russian separatists affiliated with the self-proclaimed unrecognized Donetsk and Luhansk People's Republics, and the post-revolutionary Ukrainian government. Until the ongoing war, the Donbass was the most densely populated of all the regions of Ukraine apart from the capital city of Kiev.

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