The total Eclipse on May 29, 1919 in South America was used by British astronomer Arthur Eddington to prove that light rays from distant stars are bent by the gravitational field of the Sun. Eddington's observations confirmed that Einstein's Theory of General Relativity that massive objects like the Sun exert a massive gravitational field that warp time, space and even light (image below). Eddington was able to observe that distant stars apparent position had changed when the Sun was blocked out during the eclipse of 1919. He observed that light from these stars was distorted off their normal path by the Sun's gravity. The eclipse was an important necessary event because normally the brightness of the Sun blocks out light from distant stars because their light is normally fainter than the Sun's.
So as we look (or don't look) at the eclipse on August 21, 2017, those of us in the science community will be thinking fondly of the most historic eclipse in history. The eclipse of 1919 when one of Einstein's theories was yet again proven correct. To date, all of Einstein's theories have been proven correct. It is an amazing testament to how brilliant he really was.