Christmas in July, also known as Christmas in Summer in the Northern Hemisphere and Christmas in Winter or Midwinter Christmas in the Southern Hemisphere, is a second Christmas celebration held on July 25 that falls outside the traditional period of Christmastide. It is centered on secular Christmas-themed activities and entertainment, including small gatherings, seasonal entertainment, and shopping. July Christmas celebrations typically accommodate those living in the Southern Hemisphere, where they experience winter at that time.

In a journal entry dated December 1827, colonial settler James Macarthur reflected on the challenges of observing Christmas during the Australian summer and proposed relocating its traditional “eating and drinking” aspects to a cooler season:

“I have always thought it would be a public benefit … to change the eating and drinking part of this festival to a more temperate season of the year … In the month of June there is no operation of importance going forward … John Bull might then indulge as freely as at home without endangering his health.”

This entry, written while at Port Stephens and contained in Macarthur’s correspondence to his family, represents among the earliest documented colonial suggestions for celebrating Christmas mid‑winter in Australia—nearly a century before mid‑winter “Christmas in July” events became formalized.

Werther, an 1892 French opera with libretto by Édouard Blau, Paul Milliet, and Georges Hartmann, had an English translation published in 1894 by Elizabeth Beall Ginty. In the story, a group of children rehearse a Christmas song in July, to which a character responds: "When you sing Christmas in July, you rush the season." It is a translation of the French: "vous chantez Noël en juillet... c'est s'y prendre à l'avance." This opera is based on Goethe's The Sorrows of Young Werther. Christmas features in the book, but July does not.

In 1935, the National Recreation Association's Journal Recreation described what a Christmas in July was like at a girl's camp in Brevard, North Carolina, writing that "all mystery and wonder surround this annual event."

The term, if not the exact concept, was given national attention with the release of the Hollywood movie comedy Christmas in July in 1940, written and directed by Preston Sturges. In the story, a man is fooled into believing he has won $25,000 in an advertising slogan contest. He buys presents for family, friends, and neighbours, and proposes marriage to his girlfriend.

In 1942, the Calvary Baptist Church in Washington, D.C. celebrated Christmas in July with carols and the sermon "Christmas Presents in July". They repeated it in 1943, with a Christmas tree covered with donations. The pastor explained that the special service was patterned after a programme held each summer at his former church in Philadelphia, when the congregation would present Christmas gifts early to give ample time for their distribution to missions worldwide. It became an annual event, and in 1945, the service began to be broadcast over local radio.

The U.S. Post Office and U.S. Army and Navy officials, in conjunction with the American advertising and greeting card industries, threw a Christmas in July luncheon in New York in 1944 to promote an early Christmas mailing campaign for service men overseas during World War II. The luncheon was repeated in 1945.

American advertisers began using Christmas in July themes in print for summertime sales as early as 1950. In the United States, it is more often used as a marketing tool than an actual holiday. Television stations may choose to re-run Christmas specials, and many stores have Christmas in July sales. This is partly because most bargainers sell Christmas goods around July to make room for next year's inventory.

https://en.wikipedia.org/wiki/Christmas_in_July