Pyongyang, North Korea’s capital city, is a vast symbol of the supposed might of the Democratic People’s Republic of Korea—filled with monolithic buildings, huge boulevards and symbols of the dictatorship’s power. But during the mid-1990s, it was filled with something else: starving people. Reports of the time note the presence of hungry workers who roamed the streets, listlessly trying to walk off the effects of near starvation.

They were victims of one of North Korea’s most mysterious disasters—a huge famine that affected the 25 million-person country due to poor planning, isolation and a misguided policy of self-sufficiency. But though the famine may have killed many millions, its true extent has never been understood in the West, and it appears never to have been publicly acknowledged by North Korean officials.

The famine’s roots date to 1948, when the Democratic People’s Republic of Korea was created. North Korean farmland and weather conditions aren’t ideal for producing food, but at first, the new country was able to sidestep those issues by aligning itself with the Soviet Union and socialist allies, which provided substantial aid and imported food and cheap fuel.

The government strictly controlled the distribution of all food, doling out rations to city dwellers and people in the military. (Farmers were given a share of their own crop instead.) Rations were determined not by need but by political power. Elites and those loyal to the government were given more food than the elderly, children and others. Over the years, however, as the USSR began to crumble, the aid that fed North Koreans faltered and then stopped altogether.

As the DPRK became increasingly isolated, its leader, Kim Il Sung, turned to a national policy of “juche,” or self-reliance. This catchphrase hypothetically celebrated a North Korea that was capable of doing everything itself, but when it came to food, the DPRK was anything but self-reliant. (Analysts think that the juche doctrine was primarily an excuse for the dictator to consolidate power.)

Under the juche philosophy, North Korea’s people were expected to feed themselves. The DPRK’s government assisted by distributing chemical fertilizers designed to make farmers’ crops even more fertile. But when the USSR collapsed, so did access to inexpensive fuel. The DPRK’s fertilizer production ground to a halt, the victim of fuel shortages, and farm yields plummeted. “The government started a campaign urging citizens to consume less,” The Atlantic’s Jordan Weissmann writes. “Its cheery slogan: ‘Let’s eat only two meals a day.’”

In 1995 and 1996, a warm El Niño weather pattern brought widespread flooding to North Korea. This was catastrophic for North Korea’s supposedly self-reliant farmers: a whopping 15 percent of the country’s already scant arable land was destroyed. Then, the dictatorship reduced the amount of grain farmers were allowed to keep for themselves in an attempt to save food. Rather than eat less, farmers hid grain instead, which led to even less available food.

The lack of food panicked the North Korean leadership, and in a rare move, they asked the international community for food aid. At first, countries and aid organizations hesitated, surprised by the isolated country’s sudden plea for food. Eventually, though, they provided the requested aid—much of which was stolen and redistributed among the country’s elite instead of making it to hungry North Koreans. As Weissman writes, “Farmers stole their own crops. Elites stole the aid. Impoverished Koreans starved.”

As food lessened, the government stopped providing rations altogether and prioritized feeding the military over civilians. North Koreans began eating grass and foraging for wild food to survive. As many as several hundred thousand North Koreans crossed the borders to countries like China in a desperate search for food, despite a nationwide travel ban.

Meanwhile, malnutrition affected people of all ages. When a relief worker visited in 1997, he told The New York Times that people were reduced to eating watery gruel when they could find food at all. Discolored hair, wasted bodies and swollen eyes were common among children—telltale signs of starvation. It thought that an entire generation of kids suffered physical and mental impairments due to lack of food.

Eventually, international food aid alleviated the famine. Today, North Korea continues to rely on food aid from the international community, including the United Nations and the United States, to prop up food production. Natural disasters and weather patterns continue to leave it vulnerable to large fluctuations in food availability.

In North Korea, the famine has a state-sanctioned name: a phrase that translates to “The Arduous March.” The euphemism belies the suffering of those who starved and died during the famine and reflects officials’ refusal to acknowledge their role in the famine. North Korea’s dictatorship continues to blame the catastrophe—and the country’s ongoing food problems—on external causes.

As with so much related to the secretive state, it’s nearly impossible to estimate the number of people who perished during the famine. Experts say the figure could be as high as hundreds of thousands—or even a million, or five percent of the country’s population. And another famine might not be far away: According to Newsweek’s Jason Le Miere, drought and continued sanctions could plunge the country into another food crisis.

The United Nations estimates that two in five North Koreans lack sufficient food and access to basic healthcare and sanitation, and more than 70 percent of the population relies on international food aid to survive. A full 41 percent of the DPRK’s population is thought to be undernourished.

With that many lives on the line, will the country’s leaders learn lessons from their famished past? That remains to be seen. But for those who suffered and lost loved ones during the famine, memories of the misery of starvation will not be easily forgotten.