Thomas Edison was known for his wacky publicity stunts, but during the Christmas of 1880 he went for the sentimental rather than shock value. Edison had his incandescent light bulbs pretty well figured out by then, and was on the lookout for a way to advertise them. Brian Murray’s article “Christmas Lights and Community Building in America” describes Edison’s marketing trick during that holiday season. To display his invention as a means of heightening Yuletide excitement, he strung up incandescent bulbs all around his Menlo Park laboratory compound, so that passing commuters on the nearby railway could see the Christmas miracle. Two years later, an Edison crony named Edward Johnson displayed the first electrically illuminated Christmas tree at his home in Manhattan.

The tradition of lighting lights in the winter months didn’t start off with aesthetics in mind. December is the darkest month of the year with the shortest days. People living without central heating in the 12th century were understandably unhappy when the sun went down and plunged them into the cold depths of night. Brian Murray’s article tells us that back during the winter of 1184 was
the first recorded lighting of the Yule Log in Germany. The burning log was seen as a symbol of the sun’s promise to return. It probably didn’t hurt that a big burning hunk of wood makes for a pretty good heat source.

Unfortunately, the only way to add Christmas lights to a tree back then was with candles. Obviously, this was a pretty bad idea. By 1900, electric Christmas lights were becoming a viable option for the extremely rich.
A single string of electric lights at that time cost $12 —around $300 in today’s money. They were so expensive, the first known ad for the lights suggested renting them for holiday displays!
Twenty-five years later, demand was up. There were 15 companies in the biz of selling Christmas lights, and in 1925 they formed a consortium called the NOMA Electric Corporation, the largest Christmas light manufacturer in the world. They worked hard to bedazzle, becoming the world’s biggest manufacturer of the bubble light—arguably the first great mass-produced tacky Christmas decoration.

With NOMA, the tacky Pandora’s box had opened, and even people who didn’t spring for bubble lights have done wonders with the decidedly more standardized sets we all know
today. Once they were weatherproofed for outdoor use, it was only a matter of time before they were stapled to every square inch of house, hearth, tree, even truck.
The basic foundation of the Christmas light, the incandescent bulb, hardly changed for nearly a century, and is only now undergoing is first major revolution, as we start replacing our old tungsten lights with energy-efficient LEDs. One thing’s for sure: No matter what the technology at hand, no matter what the reason to celebrate, the human desire to light up trees and houses in the cold darkness of the winter months will forever be a source for amazing—and often hilarious—innovation.

Excepts from Gizmodo’s “Christmas Lights, The Brief and Strangely Interesting History Of”
The entire article can be viewed here