The custom goes back to the use of candles to decorate the Christmas tree in upper-class homes in 18th-century Germany. Christmas trees displayed publicly and illuminated with electric lights became popular in the early 20th century. By the mid-20th century, it became customary to display strings of electric lights
The Christmas tree was adopted in upper-class homes in 18th-century Germany, where it was occasionally decorated with candles, which at the time was a comparatively expensive light source. Candles for the tree were glued with melted wax to a tree branch or attached by pins. Around 1890, candleholders were first used for Christmas candles. Between 1902 and 1914, small lanterns and glass balls to hold the candles started to be used. Early electric Christmas lights were introduced with electrification, beginning in the 1880s.
The illuminated Christmas tree became established in the United Kingdom during Queen Victoria's reign, and through emigration spread to North America and Australia.
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The first decorated trees were adorned with apples, white candy canes and pastries in the shapes of stars, hearts and flowers. Glass baubles were first made in Lauscha, Germany, by Hans Greiner (1550-1609) who produced garlands of glass beads and tin figures that could be hung on trees. The popularity of these decorations grew into the production of glass figures made by highly skilled artisans with clay molds.
The first American-made glass ornaments were created by William DeMuth in New York in 1870. In 1880, Woolworth's began selling Lauscha glass ornaments. Other stores began selling Christmas ornaments by the late 19th century and by 1910, Woolworth's had gone national with over 1000 stores bringing Christmas ornaments across America.