The Livonian language, which survived conquests of what is now the tiny Livonia province of Latvia by the Danes, the medieval Knights of the Sword, the Teutonic Knights, the Lithuanians, the Poles, the Swedes, the Russians, the Prussians, the Russians again, the Germans, the Russian revolution, the Nazis, and the Soviets, is down to one last native speaker.
In the end, Stalin killed Livonian, deporting the Livonians who hadn't been slaughtered in two world wars to Siberia and forbidding official instruction in the language. Though Livonian culture survives (barely), with one native speaker left, the language will soon be as dead as Cornish and Etruscan. It is, unfortunately, only one among many.
H/t: Walter Olson, via Twitter.