Have people died from speeches

Answer

In a way yes. President Henry Harrison died giving his inaugural address because of the combination of freezing weather and the length of time he was exposed to it giving his long speech. He died shortly after he was hospitalized after he caught pneumonia.

Answer

That is really hard to say, I don't believe that there are records kept that will give that answer. You can estimate that many millions died as a result of speeches by Adolf Hitler and Josef Stalin.