For 110 years, the numbers stood as gospel: 618,222 men died in the Civil War, 360,222 from the North and 258,000 from the South — by far the greatest toll of any war in American history.

But new research shows that the numbers were far too low.

By combing through newly digitized census data from the 19th century, J. David Hacker, a demographic historian from Binghamton University in New York, has recalculated the death toll and increased it by more than 20 percent — to 750,000.

The new figure is already winning acceptance from scholars. Civil War History, the journal that published Dr. Hacker’s paper, called it “among the most consequential pieces ever to appear” in its pages. And a pre-eminent authority on the era, Eric Foner, a historian at Columbia University, said: