Did you know Thomas Edison was behind the first Christmas light display?
Yes, it is true, and his involvement resulted from his desire to put "a spotlight" on his recently developed incandescent light bulb.
1880
In 1880 in Manhattan, Edison laid out underground wire for 8 miles to power strings of light around the outside of his New Jersey laboratory.
Edison contacted local media outlets and spoke with one New York journalist about his plans, but asked that he not tell the public just yet. The plan was to have the display go live in January, but the journalist predictably leaked the story (for a fee!), and Edison and his team moved up their timeline.
Today
Even with the massive display outside Menlo Park in Manhattan, the lights we expect to see today during the holidays did not hit select consumers until 1902 by general Electric, founded by Edison.
They were expensive, though, and only became available to the mass market several decades later.
The rest is, as they say, history!