This day in May 19, 1780 the skies of New England went dark at 9 in the morning. American Heritage magazine describes the beginning of the day with a pink hue that darkened as the morning passed until noon reached an incredible darkness.
An article in Harper's Magazine cited by the Smithsonian, mentions the black out specifically with this: "Birds went to roost, cocks crowed at mid-day as at midnight, and the animals were plainly terrified."
Mainers and New Englanders didn't know what to make of the day that the skies went dark but it caused confusion and fear of the apocalypse. Superstition and religion became the way to reason what happened, they interpreted it as Judgment Day, the day that they would meet their fate of death and destruction as described in the Bible as a part of the apocalypse.
According to an account from Celebrate Boston, the sun and moon where unusually red. The end of the day at midnight saw the passing of the darkness when stars appeared in the sky after a day of no sky.
So, what was the actual cause of this 'Dark Day of 1780' in New England? The cause is believed to be smoke from forest fires in the west. There's even thoughts that it was a combination of fire smoke and fog. American Heritage cites a study by the International Journal of Wildland Fire who performed a tree ring study finding that there was a vast forest fire in southern Ontario and in other parts of Canada around this time along with a drought. These conditions could make for a large smoke cloud to pass over New England and in large amounts.
Plenty of people were still very worried despite the passing of the darkness, including religious groups like the Shakers of New York. They saw this as a sign and started over two years of missionary service throughout the region to convert people to their sect of Christianity.
As fast as the dark day came and went, many were truly shaken by the event and their thoughts and fears now live in folklore and poems that were carried into the following generations.