Cakes were eaten to celebrate birthdays long before they were called “birthday cakes.” Food historians confirm ancient bakers made cakes (and specially shaped breads) to mark births, weddings, funerals, harvest celebrations, religious observances, and other significant events. Recipes varied according to era, culture, and cuisine. Cakes were usually saved for special occasions because they were made with finest, most expensive ingredients available to the cook. The wealthier one was, the more likely one might consume cake on a more frequent basis.
The birthday cakes we enjoy today are inventions of the 19th century. These were enjoyed by middle and upper classes. People with less money and poorly stocked larders also made birthday cakes. Their were not quite the light, fluffy iced concoctions served by their wealthier contemporaries. In all places and times, cooks blessed with creativity and “make do” spirit generated some pretty fine foods in the name of love. This was also true in War time.
The practice of eating cake on a regular basis by “average people” became possible in the 19th century. Why? The Industrial Revolution made many baking ingredients more affordable (mass-production) and readily available (railroads). It also introduced modern leavening agents, (baking soda, baking powder), a variety of cheaper substitutions (corn syrup for sugar; margarine for butter), and more reliable ovens.
Cake history expert Simon R. Charlsey makes this observation:
“Birthday cakes might still in the nineteenth century be of the same kind [as wedding cakes], but as their use spread, their composition became typically simpler. For preference of the child or other person celebrating, or of the cook, or whatever the confectioner had used for a decorated shop cake.”
—Wedding Cakes and Cultural History, Simon R. Charsley [Routledge:London] 1992 (p. 61)
“The dominant English culture in America shaped birthday patterns for some time. Colonial birthdays were enjoyed by privileged adults, who feasted well, or at the very least, shared a glass of wine and a small slice of fruitcake with friends. Children’s parties echoed the adult formats…In the new age of democracy, birthdays did not remain class-limited. As the nineteenth century progressed, a number of factors reshaped the events. The growth of industry, elevated urban material standards, and emering middle class culture amde more elaborate birthday celebrations increasingly attractive. Changing notions of the nature of childhood stimulated a new style of young people’s parties…Ice cream and cake became defining elements, whether after a meal or as the centerpiece of a party…Although fruitcakes and rich, yeasted cakes were the traditional English festive cakes, the modern form of birthday cake originated in American kitchens in the mid-nineteenth century. In contrast to their European counterparts, American women were active home bakers, largely because of the abundance of oven fuel in the New World and the sparsity of professional bakers. By the late 1800s, home bakers were spurred further by several innovations. The cast-iron kitchen stove, complete with its own quickly heated oven, became standard equipment in urban middle-class homes. Women in towns had more discretionary time, compared to farm-women, and they had an expanding social life that required formal and informal hospitality. Sugar, butter, spice, and flour costs were dropping. Improved chemical leavening agents, baking powder among them, enabled simpler and faster baking and produced a cake of entirely different flavor and texture. A cake constructed in layers, filled and frosted, became the image of the standard birthday cake. One observer of the early 1900s compared bubbly soap lather to “the fluffiness of a birthday cake” and snowy, frost covered hills to iced birthday cakes…Writing on birthday cakes began with professional bakers and caterers, who were proliferating in growing cities. The cakes of the late 1800s were decorated with inscriptions like “Many Happy Returns of the Day” and the celebrant’s name, a tradition that continues into the twenty-first century. Sometimes the cake was home-baked but then decorated by a specialist…The phrase “Happy Birthday” did not appear on birthday cake messages until the popularization of the now-ubiquitous song “Happy Birthday to You” (1910). Cookbook authors began to recommend decorating with birth dates and names and offered instruction on how to make colored frostings…By 1958, A.H. Vogel had begun to manufacture preformed cake decorations. Inexpensive letters, numbers, and pictorial images, such as flowers or bow, with matching candleholders were standard supermarket offerings.”
—Oxford Encyclopedia of Food and Drink in America, Andrew F. Smith editor [Oxford University Press:New York] 2004, Volume 1 (p. 99-100)
“Small, colored candles became an integral part of the American birthday cake. An American style guide of 1889 directed, “At birthday parties, the birthday cake, with as many tiny colored candles set about its edge as the child is years old, is, of course, of special importance.” The modern use of candles on a special cake may be connected to the German tradition of Kinderfest, dating from the fifteenth century, a time when people believed that on birthdays children were particularly susceptible to evil spirits. Friends and family gathered around protectively, keeping the cake’s candles lit all day until after the evening meal, when the cake was served. The candles were thought to carry one’s wished up to God. This German observance was brought to colonial Pennsylvania and was later reinforced by the influence of British-German fashions from Queen Victoria’s court.”
—ibid (p. 99)
American cookbooks bear this out. In the last quarter of the 19th century, we find a veritable explosion of simple cake recipes. Mrs. Porter’s New Southern Cookery Book  contains several of these items. Many have inventive names. Curiously? None of them are called “birthday cake.” The recipes provided by Mrs. Porter that are most like today’s birthday cakes are: “Silver cake,” “Gold cake,” and “Little Folks’ Joys.”
“Little Folks’ Joys
One cupful of white sugar, one cupful of rich sour cream, one egg, two cupsful of flour, half a teaspoonful of soda, and flavor to taste; bake about half an hour; nicest eaten fresh and warm.”
—Mrs. Porter’s New Southern Cookery Book, Mrs. M.E. Porter, 1871 , [Promentory Press:New York] 1974 (p. 242)
Into a pound of dried flour, put four oucnes of butter, flour ounces of sugar, one egg, a tea-spoonful of baking powder, and sufficient milk to wet to a paste. Put in currants, and cut in cakes. Sprinkle colored caraway seeds on top, and bake them a light brown.”
—Jennie June’s American Cookery Book, Mrs. J. C. Croly [Aemrican New Company:New York] 1878 (p. 203)
“Birthday Cakes for Children.
One and one-half cups of sugar, a half-cup of butter or clarified drippings, two eggs, one cup of milk, two cups flour, one teaspoon baking powder, one-half teaspoonful of vanilla. Beat together the butter and sugar, add the eggs, then the flour, baking-powder and nutmeg sifted together. Place in small well-greased tins and just before putting into the oven drop a few seeded raisins on top of each cake. Spread on the top a few drops of boiled icing and on top of these some colored candies or cinnamon drops, as they are favorites with the little folks. Aunt Mary.”
—The Blue Ribbon Cook Book, Annie R. Gregory [Monarch Book Company:Chicago] 1906 (p. 258)