A Civil War-era Santa Claus even visited the camp, handing out oranges, apples and other fruit that were hard to come by during the war and in the winter.
But the wounded, lying on straw and covered with wool blankets inside tents as the doctors and nurses of Antietam Army Hospital tended to them, served as a reminder of the bloody war that would continue the next day.
"Normally on Christmas Day, soldiers laid down their arms and tried their very best to forget about the war," said Kirk Davis, portraying Dr. Letterman, a director of medicine and commander of the infantry during battles.
Tayamentasachta Environmental Studies Center on Leitersburg Street was the site for a Civil War Christmas Encampment over the weekend, sponsored by the Greencastle-Antrim Chamber of Commerce as part of the borough's Heritage Christmas celebration.
Nearly 200 people toured the weekend encampment set up by a dozen members of Vincent's Brigade of the Maryland Volunteers re-enactors.
Set up to look like an Army hospital, the encampment included a guard stationed at the base of a small hill where soldiers practiced loading their black powder rifles and firing them.
The guard protected the doctors and nurses and the hospital's supplies from Confederate raids, Davis said.
Doctors and nurses were on duty Christmas Day like any other day during the Civil War, even though fighting was minimal through the cold weather months, Davis said.
The few medical instruments and drugs used in that day were on display at the encampment and the Civil War-era doctors told gruesome but true stories of wounded soldiers' suffering during the war that had claimed 300,000 men by 1863.
Total fatalities of the Civil War, which ended in 1865, was 620,000, Davis said.
On Sunday, the atmosphere was a little more relaxed as both sides came together to celebrate the holiday. In some cases, families who fought on opposite sides, which was common among those who lived along the Mason-Dixon line, were reunited for the day, Davis said.
"It was a different war completely. It was brother against brother and family against family," he said.
His own son, Patrick, 13, decided to fight for the Confederates despite the Union calling of his father and two brothers.
"I like being a Confederate soldier because they're more interesting," the teen said.
But one of his reasons for fighting on the opposite side was purely superficial.
Shouldering a rifle and wearing a well-worn uniform consisting of a brown wool coat with gold buttons, brown wool pants, a black hat and brown boots, Patrick Davis said he prefers his understated uniform to the Union's ornate navy blue uniforms.