The use of Christmas tree lights took off after the second world war thanks to the extension of electrification but how and where did this Christmas light tradition begin?
The custom can be traced back to the 16th century when, according to legend, Martin Luther tied candles to the branches of his tree after being inspired by a starry Christmas Eve sky.
The tradition of bringing decorated trees into homes for Christmas originated in Germany a century later but only became popular in America in the 19th century following the arrival of German settlers.
Christmas trees became popular on both sides of the Atlantic in the mid-19th century thanks to images of important people around their candlelit trees: Queen Victoria and her family in the UK and President Franklin Pierce in the USA. However, it was difficult to keep the candles attached to the branches, even following the invention of the clip-on candleholder in 1878. There was also the major risk posed by having a highly flammable tree in the home, which meant that people lit their candles for no more than half an hour at a time and always had a bucket of sand or water at the ready in case of emergency.
Despite these precautions, fires were common and some insurance companies refused to pay out for Christmas tree fires. Yet this hazardous practice continued until well into the 20th century, despite the invention of strings of lights by Thomas Edison in 1879. The first use of such lights for decoration was in 1882, when Edison’s business partner Edward Johnson hung 80 blinking red, white and blue hand-wired lights around a rotating Christmas tree in his parlour and enchanted passers-by.
President Grover Cleveland used lights on the White House Christmas tree in 1895, and overnight, electric Christmas tree lights became a national sensation, helping to overcome the widespread fear at the time that dangerous vapours would seep into homes through the electric lights and wires. However, they were prohibitively expensive for most people – it cost about US$ 300 (around US$ 2,000 in today’s money) to light a single tree, as each individual light had to be wired by an electrician.
In 1903, the General Electric Company started selling a pre-assembled kit consisting of eight green pre-wired porcelain sockets, eight Edison miniature base coloured glass lamps and a handy screw-in plug for easy attachment to a nearby wall or ceiling light socket that could be rented from some department stores for about US$ 1.50 a strand.
However, candles continued to be the most popular means of lighting Christmas trees, until a tragic fire in New York City in 1917 gave 15-year-old Albert Sadacca the idea of adapting the novelty lighting his parents sold for Christmas trees. Only a hundred strings of lights sold in the first year, however after Albert started to paint the lights in different colours, the business began to take off. Sadacca subsequently founded the snappily-named National Outfit Manufacturers Association, a trade group of several small companies that consolidated into the NOMA Electric Company in 1926. NOMA was the largest Christmas light company in the world until the mid-1960s.
Unfortunately, many of the earliest Christmas lights burned so hot that they were about as dangerous as the candles they were advertised to replace.
A key property of modern Christmas lights is the ability to twinkle. Twinkling lights were first introduced in the 1920s, consisting of a simple thermostat – once the lights were plugged in, a strip of metal inside the bulb was heated until it bent, breaking the circuit and extinguishing the light. As the light cooled down, the strip of metal bent back, reconnecting the circuit and relighting the light. Modern lights use an integrated circuit, and, while the bulbs are still connected in series, a shunt within each bulb prevents the entire string of lights from going out if one bulb fails.
True outdoor Christmas lights were not introduced to the public until 1927 – almost 45 years after the first electric tree lights were demonstrated.
Since 1998 Christmas lights have predominantly been LEDs with much longer lifetimes – up to 100,000 hours – than their incandescent predecessors. LED lights are much more efficient as they use 95% less energy and are also shock and vibration resistant. Some models are even moisture resistant for outdoor use. LEDS are also environmentally friendly as the strands can be recycled.