Humans, after adopting a more settled lifestyle, began to rely on barley and wheat, the first cereals to be deliberately cultivated, in addition to the fluid they consumed before. This new fluid became a crucial part of societal, religious, and economic life and was the primary beverage of the earliest civilizations. This was the drink that first helped humanity progress towards modernization: beer.
Pleasure—it is beer. Discomfort—it is an expedition.
—Mesopotamian proverb, c. 2000 BCE
The mouth of a perfectly contented man is filled with beer.
—Egyptian proverb, c. 2200 BCE
That pictogram you see is from a seal found at Tepe Gawra in Mesopotamia, dating from around 4000 BCE. It depicts two figures drinking beer through straws from a large pottery jar. Yes, back in the day, beer needed straws. Ancient beer, you see, had grains, chaff, and other kinds of debris floating on its surface, thus necessitating straws. It is unknown when the first beer was brewed. Beer was already widespread in the Near East by 4000 BCE, but there was almost certainly no beer prior to 10,000 BCE. How exactly did that transition happen? And how was beer invented? Or was it discovered? The answers to these questions are not quite certain.
Since around 150,000 years ago, when anatomically modern humans, or Homo sapiens sapiens, emerged in Africa, water has been humankind's primary drink. The fluid constitutes two-thirds of human body matter, and no life on Earth can survive without it. Humans, after adopting a more settled lifestyle, began to rely on barley and wheat, the first cereals to be deliberately cultivated, in addition to the fluid they consumed before. This new fluid became a crucial part of societal, religious, and economic life and was the primary beverage of the earliest civilizations. This was the drink that first helped humanity progress towards modernization: beer. Beer's birth occurred during a time characterized by rapid transformation and upheaval, when groups of people stopped traveling and began to settle down, leading to a rapid and striking rise in the complexity of societies and the emergence of cities. Beer is a tangible connection to humanity's past, and its history is strongly linked to the beginnings of civilization.
The ability to store cereal grains began to encourage people to stay in one place. Having gathered a large quantity of grain, they were reluctant to leave it unguarded. and, thus it is argued, began permanent settlements. Even though the people who lived in these settlements pursued wild animals such as gazelles, deer, and boar, skeletons suggest that the majority of their diet consisted of plants like acorns, lentils, chickpeas, and other grains, which were collected rather than grown intentionally. Cereal grains came to be viewed significantly – and drove permanent settlements as the norm even more – because of the discovery of two properties. The first was that grain soaked in water, so that it starts to sprout, tastes sweet. At a time when sources of sweet were few (outside of seasonal fruits and rarely available honey), the sweetness of this "malted" grain came to be highly valued. The second was that when this gruel was left to stand for a few days, it underwent a curious change, especially if it was made using malted grain; it would become slightly effervescent and pleasantly inebriating as the wild yeasts in the atmosphere converted the sugar in the gruel into alcohol. To put it simply, the gruel had converted into beer!
To be sure, it may not have been the first time humans tasted alcohol. Alcohol may have been made from the accidental fermentation of fruit juice (wine) or water and honey (mead) when people tried to store fruit or honey. Fruits are only available at certain times of the year and don't last long, while wild honey is hard to come by in large amounts. Wine and mead couldn't be stored for long periods of time until pottery was invented around 6000 BCE. Beer, however, could be produced from cereal grains, which were plentiful and could be stored for later use, allowing for beer to be made in larger quantities whenever needed. Long before pottery became available, beer could have been made and stored in pitch-lined baskets, leather bags or animal stomachs, hollowed-out trees, large shells, or stone vessels. In fact, Sahti, a traditional beer made in Finland, is still brewed in hollowed-out trees today.
The beer thus formed began to get better by trial and error. The more malted grain there is in the original gruel—as ancient man discovered—and the longer it is left to ferment, the stronger the beer. Records from Egypt and Mesopotamia show that brewers carried their own "mash tubs" because they had discovered that using the same containers over and over again for brewing promoted fermentation (because yeast cultures took up residence in the container's cracks and crevices). By adding berries, honey, spices, herbs, and other flavorings to the gruel, early brewers discovered and made newer and newer kinds of beer. Later Egyptian records show as many as 17 different kinds of beer, including those named as fancifully as "the beautiful and good," "the heavenly," and "the joy-bringer." Mesopotamia, by 3000 BCE, had about twenty different kinds of beer! The Mesopotamian brewers had the ability to adjust the flavor and color of their beer by adding various amounts of bappir, which is also known as beer bread. This beer bread was made by molding sprouted barley into lumps similar to small loaves and then baking it twice until it was dark brown and crunchy. This unleavened bread could be kept for a long period before being crushed and added to the container of the brewer. It has been documented that bappir was kept in public warehouses and was only eaten during times of food scarcity; it was not really consumed as a food but was a practical way to conserve the primary ingredient for brewing beer!
This has led to some debate about whether bread was an offshoot of beer-making or if bread was an ingredient in beer-making. Classic chicken-and-egg problem. It is probable that both bread and beer were developed from gruel. A thick gruel could be cooked in the sun or on a hot stone to create flatbread; a thin version could ferment and become beer.
Tl;dr: Bread is essentially solid beer, and beer is essentially liquid bread.