He didn't especially feel a part of history that day, even as he passed the old soldiers bivouacked along the Harrisburg Road. After all, he was a Gettysburg native, and the battlefield had been his backyard, a place where as a child he scavenged for Civil War relics.
Today, Tate is 94, the same age as many of the veterans he had seen in 1938. And he is now keenly aware, as they were, of the gravitas of this once-blood-soaked ground. He spends most of his waking hours walking it, in his trademark blue straw hat and button-down shirt, as a licensed battlefield guide.
He just celebrated his 60th anniversary in that vaunted rank, consisting of 150 historians who had to pass rigorous oral and written exams to win the job.
On a recent tour with a family from Virginia, Tate lifted his multihued cane in a sweep across the valley toward the Blue Ridge Mountains, and explained how the Confederate Army under Gen. Robert E. Lee pushed north and then east toward the Pennsylvania Capitol.
"Their objective was to capture Harrisburg," said Tate, segueing through time from 1863 to 1938, then to 1941. That year, as a member of the Pennsylvania National Guard, he rode horseback 20 miles in a snowstorm from Harrisburg to Fort Indiantown Gap with one of the last mounted cavalry units in the U.S. Army.
"We used McClellan saddles," Tate recalled, referring to the Union general for whom the saddles were named. "We were not that removed from the Civil War."
When he started out in the 1950s, he said, guides "hustled" tours on the Gettysburg town square, looking for history-seeking families in Studebakers and Dodges with out-of-state plates. He could make $4 a car back then.
"You had to sell yourself," said Tate, who once also worked as a Westinghouse salesman and an IBM serviceman.
Under the auspices of the National Park Service, guiding has become a more orderly operation, and somewhat more rewarding. A paid battlefield guide now makes $55 per carload, and more for larger bus tours.
But the guides still compete in a friendly way. For Tate, this means leading two tours - each lasting at least two hours - five days a week during the summer.
Despite the rigors, Tate, who lost his wife, Eleanor, in 2003, has no plans to retire.
"I don't think he could retire," said Clyde Bell, a park ranger and guide supervisor. "Visitors send positive comments about him, the guides all love and respect him. This is his family."
Tate says he likes meeting new people every day, hearing their stories, finding out if they had ancestors in the Civil War - though fewer say they do these days. He isn't sure why.
"I hope I give them a sense of what happened here and what a sacrifice the men went through for their country," he said.
On a recent weekday, Tate ferried John and Deborah Denice and their 12-year-old twins, Kevin and David, of Ashburn, Va., around the battlefield. Guides typically drive visitors' cars so, as passengers, they can concentrate on the landscape. Age notwithstanding, Tate commanded the driver's seat of the minivan, and neatly navigated the winding roads of the 6,000-acre park, stopping at key points.
Standing by a cannon at the North Carolina monument from the Confederate's-eye view of Pickett's Charge, Tate described how the mounted guns were loaded and fired. He then pulled out a picture of drummer boy Johnny Shiloh, believed to be the youngest soldier at Gettysburg. The Denice boys drank it in.
"Twelve thousand men went out on that field and only 4,000 came back," said Tate. Turning to David and Kevin, he marveled: "Imagine that, boys."
From there, it was on to Little Round Top, Devil's Den, and the Valley of Death, where the Union forces held off the Confederate assault.
Tate explained how difficult it was for generals to communicate during the Civil War and pivoted to his own story as a radio operator in Marseilles, during World War II. He clicked out several lines of Morse code for his rapt audience.
"I don't think kids get much history in school," Tate said on his way back to the van. The Denice boys, Civil War buffs both, were able to discuss the finer points of the war, like the difference between Union and Confederate bullets.
He stopped along Cemetery Ridge for the Union view of Pickett's Charge on the final day of the three-day conflict.
"Picture the line of Confederates a mile wide," he said. "You hear the crack of guns, the smell of sulfur, arms and legs flying, the Rebel Yell."
Between tours, Tate sat on a bench outside the visitors center and took a breather, though he spent it pulling a century of experiences from his memory bank.
He recalled seeing President Dwight Eisenhower and British Field Marshal Bernard Montgomery walking the battlefield. He ran into first lady Mamie Eisenhower at the A&P.
Then there are the indelible memories of the 1938 reunion, of the lines of A-frame tents. There were too many people and too little time for conversation, he said, but the images remain powerful.
When the anniversary celebration was over, many veterans left town by train, from the same station where President Abraham Lincoln arrived to give his Gettysburg Address four months after the battle.
Tate was there to see the aging veterans off.
"That was one of the most impressive things," he said. "At the end of the last car there stood a Confederate and a Union soldier waving to the people as the train pulled out.
"To look at that, it was like they were fading into history."
To see a video of guide Jim Tate and Civil War images, go to www.philly.com/Tate
Contact Amy Worden at 717-783-2584, firstname.lastname@example.org, or follow @inkyamy on Twitter.