Bill, I'm the cowboy who never saw a cow. Never roped a steer 'cause I don't know how. And I sure ain't fixin' to start in now. Yippee i oh ti-ay. But my hunch is that stampede probable came from the Spanish 'estampido', which may have its own connection to the Italian.... Many of our cowpokey terms seem to have some kind of Vaquero-id origin. But I learned Spanish watching dubbed Japanese monster movies on Univision when I was a kid so who knows how reliable that is. (Or my dancing.)
Victor, the far fiasco 'planation was amazing.
Ever tried, ever failed, no matter. Try again, fail again, fail better.--Samuel Beckett