On this day in economic and financial history...

Most Americans take Thanksgiving for granted, but this important holiday has undergone numerous changes throughout the years. These days we celebrate annually on the fourth Thursday of November, but the nation's first official Thanksgiving was proclaimed a one-time deal. President George Washington's proclamation in 1789 set the holiday for a specific day:

I do recommend and assign Thursday the 26th day of November next to be devoted by the People of these States to the service of that great and glorious Being, who is the beneficent Author of all the good that was, that is, or that will be. That we may then all unite in rendering unto him our sincere and humble thanks, for his kind care and protection of the People of this Country previous to their becoming a Nation.

Thanksgiving holidays were proclaimed sporadically through the following decades. President Abraham Lincoln established the modern tradition by proclaiming an official celebration for the last Thursday of November in 1863, to be held annually thereafter. That day, incidentally, was also November 26. It was not until 1941 that the modern fourth-Thursday tradition was established when President Franklin Roosevelt signed a Thanksgiving bill (set to go into force the following year) into law. The first "official" fourth-Thursday Thanksgiving also took place on Nov. 26, in 1942.

Today, Thanksgiving is a major boon to certain agricultural producers, and it also signals the impending start of Black Friday, the most notable discount-shopping day of the year. More than 46 million turkeys are eaten in the United States every Thanksgiving, which is nearly a fifth of the 254 million turkeys raised in the country every year. In 2010, U.S. sales of 7.11 billion pounds of turkey generated $4.37 billion in revenue.

Butterball, a familiar name every Thanksgiving, is the country's largest turkey-producer, with 1.3 billion pounds processed in 2010. Unfortunately for investors, it remains private. However, the next-largest producer is public: Jennie-O, a subsidiary of Hormel (NYSE:HRL). It produces nearly the same amount of turkey as Butterball.

Back in black
After Thanksgiving comes Black Friday. The term "Black Friday" originated in Philadelphia during the 1960s, where huge shopping-related traffic jams led police on the streets to use the term negatively. These days it's a phenomenon: Early estimates for 2012's holiday-weekend shopping show that 139.4 million people went shopping either in stores or online. Their average purchase was $423 -- nearly a 13% rise over 2011's Black Friday-fueled frenzy. For the first time ever, online shoppers spent more than $1 billion on Black Friday. That's great news for Amazon.com (NASDAQ:AMZN), which heavily promotes its vast catalog of goods to millions of shoppers during the Black Friday period.

Black Friday also provides a powerful impetus to the Dow Jones Industrial Average (DJINDICES:^DJI). Since 1929, November's been one of the better months for the index, which gains an average of 0.84%. December's return is even better, topping all months except July with an average gain of 1.46%.

Dow component Wal-Mart (NYSE:WMT) has a lot riding on Black Friday as well. Beyond its large online operations, it's also the country's largest retailer, and the balance between these two segments will be important as online sales eat up an increasing portion of Americans' overall shopping budget. Despite employees' sporadic strike efforts, Wal-Mart remains one of the most popular retail destinations, according to social-media analysis. The other buzzworthy brick-and-mortar chain is Best Buy (NYSE:BBY), which could overcome a poor performance in 2011 with a strong 2012 holiday strategy.

Fool contributor Alex Planes holds no financial position in any company mentioned here. Add him on Google+ or follow him on Twitter @TMFBiggles for more news and insights.

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