Frye said the injured "would be in these houses and on these streets suffering."
The townspeople also suffered. Frye said many became ill and died from diseases left behind by soldiers.
Many town residents made up the Sharpsburg Rifles, Union men who were charged with protecting Maryland's border in the war.
The town's rich history qualifies it as a memorial town, he said.
"Sharpsburg, then and now and forever, will be recognized for what it is - a memorial town," Frye said.
The wreath-laying ceremony, in which 28 wreaths were placed in front of monuments memorializing wars by veterans' groups from Washington County, was the first in a series of events marking Sharpsburg's 139th Memorial Day Commemoration.
The wreath-laying was followed by a concert by the Rohrersville Band in Town Square, a parade through town and a memorial ceremony at Antietam National Cemetery.
"This is the place we come every Memorial Day," said Charles Smith of Boonsboro.
He and his wife, Marian, who have been attending the event together for more than 20 years, said they enjoy the parade and listening to the band.
Marian Smith said before attending with her husband, she used to go as a child. Her father was a member of veterans' groups and "was always in the parade," she said.
"I love it," said World War II veteran Harry E. Blair of Hagerstown.
Blair served two years in the Navy, and was stationed on the USS Chandeleur in the South Pacific. His hat bore the name of the ship along with the USS Intrepid, on which his brother was stationed.
"I praise the town and the people of the town for having this memorial, and to remember all those who have died in the wars, whether it was Antietam or any war," he said.
"Nothing takes the place of this," Blair said. "It's very, very nice."