Final answer:
The first National Public Speaking event was the Lincoln-Douglas Debates in 1858, with the first nationally significant televised event being the Kennedy-Nixon presidential debate in 1960.
Step-by-step explanation:
The first National Public Speaking event of historical significance was the Lincoln-Douglas Debates, which commenced on August 21, 1858. However, the first event that was nationally recognized in the context of modern media exposure was the televised presidential debate between John F. Kennedy and Richard Nixon on September 26, 1960. This debate highlighted the importance of public image and media in National politics, setting the precedent for the role of television in future electoral processes.