In certain cases, such as the Great Leap Forward in China (which produced the largest famine in absolute numbers), North Korea in the mid-1990s, or Zimbabwe in the early-2000s, famine can occur as an unintentional result of government policy. Malawi ended its famine by subsidizing farmers against the strictures of the World Bank. During the 1973 Wollo Famine in Ethiopia, food was shipped out of Wollo to the capital city of Addis Ababa, where it could command higher prices. In the late-1970s and early-1980s, residents of the dictatorships of Ethiopia and Sudan suffered massive famines, but the democracies of Botswana and Zimbabwe avoided them, despite also have severe drops in national food production. In Somalia, famine occurred because of a failed state.
Many famines are caused by imbalance of food production compared to the large populations of countries whose population exceeds the regional carrying capacity. Historically, famines have occurred from agricultural problems such as drought, crop failure, or pestilence. Changing weather patterns, the ineffectiveness of medieval governments in dealing with crises, wars, and epidemic diseases such as the Black Death helped to cause hundreds of famines in Europe during the Middle Ages, including 95 in Britain and 75 in France. In France, the Hundred Years' War, crop failures and epidemics reduced the population by two-thirds.
The failure of a harvest or change in conditions, such as drought, can create a situation whereby large numbers of people continue to live where the carrying capacity of the land has temporarily dropped radically. Famine is often associated with subsistence agriculture. The total absence of agriculture in an economically strong area does not cause famine; Arizona and other wealthy regions import the vast majority of their food, since such regions produce sufficient economic goods for trade.
Famines have also been caused by volcanism. The 1815 eruption of the Mount Tambora volcano in Indonesia caused crop failures and famines worldwide and caused the worst famine of the 19th century. The current consensus of the scientific community is that the aerosols and dust released into the upper atmosphere causes cooler temperatures by preventing the sun's energy from reaching the ground. The same mechanism is theorized to be caused by very large meteorite impacts to the extent of causing mass extinctions.
The Great Famine of 1315–1317 (or to 1322) was the first major food crisis that struck Europe in the 14th century. Millions in northern Europe would die over an extended number of years, marking a clear end to the earlier period of growth and prosperity during the 11th and 12th centuries. Starting with bad weather in the spring of 1315, widespread crop failures lasted until the summer of 1317, from which Europe did not fully recover until 1322. It was a period marked by extreme levels of criminal activity, disease and mass death, infanticide, and cannibalism. The famine of 1315–6 may have killed at least 30% of England's population, or at least 1,500,000 people. After the Great Famine, the Great Plague took hold in 1348. The Black Death pandemic lasted until 1351 and took, at least, another 30% of the population.
An excellent study of the 1310-50 period can be read here.
But the Great Famine only lasted about 5 years. The famine we face in the near future is forecast to last 10 years. It's interesting to note that during the Great Famine there was extreme levels of criminal activity, disease and mass death, infanticide, and cannibalism; as exactly that has been forseen for the coming famine too:
- Gayle Smith saw the famine, in the USA, brought on very quickly as stores are cleaned out within hours. There is nothing to eat so people kill others because they are hungry. After a time they begin to kill because they enjoy it. All of them become very depraved. I saw these marauding bands doing awful sadistic sexual acts, cannibalism, eating people while they are still alive and kicking. She saw the animals turn on people. The Hopi Indians have also suggested this will happen. I saw wild animals coming into the cities just devouring people. I saw mountain lions grouping together, even though they are solitary predators and timid of humans, coming into the city attacking and killing people.
- Sarah Hoffman, also in the USA, saw similar: There was no food at all, I saw people trying to get food and were completely panicked because there was no food. I saw people digging in the ground for worms and eating them because they were so hungry. Some of the people seemed to go crazy and went around in gangs killing people just for the sake of killing. Others killed for food or for things but the people who killed just to kill were absolutely terrible. They seemed like beasts, animals completely out of control as they raped, looted, burned and butchered people. I saw them go into people´s homes and drag families out who were hiding there and rape them and butcher them. There was such a fear and hatred that came upon the people — families, wives, husbands — loving ties no longer mattered; it became survival only. Husbands would kill their wives and children for food or water. Mothers would kill their children. It was absolutely horrible beyond description.
- Tom Brown Jnr, again from the USA, saw more: The world, my world, had changed. The once lush Pine Barrens that had framed the edge of the excavation were now wilted and dying. There was no sound or motion. There were no animals, no birds, and no living plants. There wasn’t any sign of water, and the only animal life seemed to be the persistent flies and carrion beetles. The air was thick with the smell of caustic chemicals and mingled with that of rotten flesh. The entire floor of the excavation was covered with bodies. Bodies of humans, young and old, badly scarred, partially clothed, and almost fully rotted. Children were tearing at the bodies. Some of the children were feeding on limbs and fingers, others were feeding on the internal organs, and all were covered in rotted flesh, blood, and maggots. As they reached the pile of fresh bodies they began to feed on the flesh with a ravenous appetite. They seemed to care little that they were eating humans. Suddenly a shot rang out from across the pit, and a young boy fell from the top of the body pile, blood pouring from his chest. Then another shot and another child fell, then another and another. Four children lay dead on the body piles, and one wounded child in apparent agony was trying to crawl to safety. Another shot and the child was dead. I watched as a group of men, dressed like bedraggled soldiers, stalked over to the edge of the pit. They scanned the pit and the walls, guns ready, as if at any moment they would be attacked. Finally three of the men entered the pit and headed for the dead children as the others stood guard. The men in the pit gutted the children, much like a deer hunter guts and field-dresses a deer. They cooked one of the children on the fire and began to feast. One of the men urinated into a can and passed the can to another, who drank it down. In the distance I could see the rubble of a city, and I cautiously got as close as possible. The once proud city lay in ruin. The air was thick and more choking than back at the pit. People lay dying and bodies were piled along gutters. Some of the bodies had been eaten. Smoldering fires held the remains of charred human bones, and people drifted around in the littered streets as if in a daze. I passed what appeared to be a store, and hanging from hooks were parts of human bodies. People seemed to be buying these as one would a side of beef. Canisters of what looked like murky water lay at the back of the store, watched over by an armed guard. Everywhere was suffering, death, and the most vile pollution.
And they say the meek will inherit the world. The meek are not going to survive this. In fact, at face value, it seems as if the only survivors are going to be the most ruthless and depraved. Not at all what you would expect from a cleansing of the population. It certainly isn't going to weed out those who do wrong and leave only the good folk. But those who survive will have fought for the privilege and they will know the desperate hardships they have endured and, hopefully, they'll turn away from terrible past and want much better for the future.