It was the greatest single natural catastrophe of the modern age. Nothing killed so many people so quickly and so easily.

By the time it had passed, the killer had taken more than 50 million lives.

It was called influenza.

The word is Italian and literally means "influence." For most of the Middle Ages, many people believed diseases were caused by the influence of astrological signs and their position in the skies. Hence, a terrible disease was blamed on the "influence" of a given set of stars. In the English-speaking world, the same recurring contagious disease came to be called la grippe.

There was nothing new about the recurring reappearance of influenza across most of the world. It came, it sickened many, it killed a few -- usually the very young or the very old -- and it moved on.

Not in 1918.

By spring of that year, the world had been at war for more than three years. What had begun as a European war had stretched across most of the rest of the world. In Europe, mighty armies had hurled themselves against each other for years with little result other than literally millions of young men dying in the effort.

In the early months of 1918, a new and virulent form of influenza began to kill as no armies could. By the time it had passed, three times more people had died of the flu than all of the bullets, bombs and poison gas put together by the armies of both sides during World War I.

To this day, we do not know for certain where the influenza outbreak began. Some think it began at Fort Riley, Kansas, in early 1918. Others think it may have begun in China or Eastern Europe. What is clear is that the outbreak in Kansas in early 1918 overtook that training camp and soon spread to other camps of closely packed soldiers preparing to leave for France.

The flu of 1918 came in waves. The first wave struck in the early spring 1918 in the training camps and other places, such as factories, where large numbers of people worked closely together. Then it seemed to die down.

President Theodore Roosevelt came to Columbus on Sept. 30, 1918, and promoted the Fourth Liberty Loan drive with a speech at the Memorial Arch at Broad and High streets. A large crowd attended, and the influenza spread among them.

By Oct. 3, 1918, Columbus health officer Dr. Louis Kahn said, "There is no need to worry so far as Columbus is concerned. The epidemic appears to be at its peak and we can look for a lessening of cases in the next few days."

The flu that affected many of the training camps did not arrive in Columbus until the last few days in September, and there had appeared to be only a few cases.

On the next day, however, people began to die. Initially, Kahn insisted schools stay open, since "there is no place safer in town than the schoolhouse."

As the epidemic spread, Kahn ordered all theaters closed indefinitely, but he allowed plans for a concert at Memorial Hall to continue after members of the chamber of commerce asked him to be lenient.

"Their argument was that only the best class of people would attend the concert and thus would not be likely to carry the influenza germs," Kahn said.

But they did, and the disease continued to spread.

As the state issued requests for meetings to cancel, Kahn suggested churches also limit their meetings. Local churches objected, asking why they should close when the saloons were permitted to stay open. Officials noted both churches and saloons were important, and both were permitted to stay open.

On Oct. 19, 1918, Kahn noted 93 people had died of influenza -- 23 of them on that day alone. He ordered the closure of the city's pool halls and canceled all public meetings for the next week.

Over the next several weeks, churches, businesses and government offices remained closed. The public schools, after reopening briefly, closed a second time and did not open again until January 1919.

From early October to the end of December 1918, 817 people in Columbus died of influenza. This is more than eight times the number who died in Columbus in the 1913 flood, four times the number who died in the cholera epidemics of the 1830s and more than twice the number of the people who died in the Ohio Penitentiary fire of 1930.

Just as the pandemic reached its peak and receded, the Great War came to an end.

Local historian and author Ed Lentz writes the As It Were column for ThisWeek Community News.