May be thousands of years before Genghis Khan the hords of steppe people conquered the territory of modern Italy in the same way mongols conquered most of Europe and Asia much later.

The fact Etruscans preserved their language could be either because they fought really well or may be had some diplomatic relations and mutual trade with the “migrants”, or both.

It’s funny we have the names of say Alexander the Great or Genghis but leaders of those long gone civilizations before them are completely unknown. May be they intermarried and the steppe people’ benevolent leader allowed some of the conquered tribes to keep their language, who knows.