The commander overseeing Lt. Wilkeson’s unit in the XI Corps, Brig. Gen. Francis C. Barlow, had surveyed the landscape and decided to abandon the position he had been assigned by his superiors. Instead, on the first day of the battle, he ordered troops, including Lt. Wilkeson and his unit, to move to higher ground, which would normally be a sound tactical maneuver.

In this case — given the Union forces available, this particular piece of higher ground and the Confederate units arrayed against them — it was a fatal choice. The position was exposed, and Union fire was returned by an overmatching number of Confederate artillery pieces. The Union unit was wiped out at a spot now known as Barlow’s Knoll, and Confederate troops took the rise.

His leg blown apart by a cannonball or shrapnel, Lt. Wilkeson was taken nearby to a community poor house serving as an ad hoc Union medical center, but the surgeons retreated from the site under the Confederate advance. There the young lieutenant died.

Carol Reardon, a noted Civil War historian, said in a telephone interview that of the approximately four-dozen reporters covering Gettysburg on both sides of the lines, Samuel Wilkeson was regarded as one of the best. “He was very well respected among the press corps,” she said.

Ms. Reardon assessed Mr. Wilkeson’s journalism and the work of other reporters in her book “Pickett’s Charge in History and Memory,” which focused on the battle’s final assault, named for Maj. Gen. George Pickett, one of the Confederate commanders who led the charge that ended in decisive defeat for the Southern forces at Gettysburg.

“Samuel Wilkeson, the skilled correspondent for The New York Times, penned the most widely clipped Northern account of the July 3 charge,” she wrote, “and even today it continues to inform histories, novels, poems and other renderings of the event.”

Ms. Reardon, who is the George Winfree professor emerita of American history at Penn State University, stressed that not all the war correspondents at Gettysburg were as careful as Mr. Wilkeson in their news gathering or as scrupulous in their retelling.