On Tuesday in a ceremony in Rome, the United Nations is officially declaring that for only the second time in history, a disease has been wiped off the face of the earth.

The disease is rinderpest.

Everyone has heard of smallpox. Very few have heard of the runner-up.

That’s because rinderpest is an epizootic, an animal disease. The name means “cattle plague” in German, and it is a relative of the measles virus that infects cloven-hoofed beasts, including cattle, buffaloes, large antelopes and deer, pigs and warthogs, even giraffes and wildebeests. The most virulent strains killed 95 percent of the herds they attacked.

But rinderpest is hardly irrelevant to humans. It has been blamed for speeding the fall of the Roman Empire, aiding the conquests of Genghis Khan and hindering those of Charlemagne, opening the way for the French and Russian Revolutions, and subjugating East Africa to colonization.

Any society dependent on cattle — or relatives like African zebu, Asian water buffaloes or Himalayan yaks — was vulnerable.