Cpl. Scott MacRae said officers found a trove of artifacts worth well over $500,000 on Friday when they searched a large, two-storey home in Fall River that had been turned into a veritable museum.
"When we first arrived, it was almost set up to be on display," MacRae said Wednesday.
"Lots of the items were from antique dealers, so there's historic value. There's value to personal collections, universities and just people in general in Nova Scotia and Atlantic Canada."
John Mark Tillmann, 51, is due in provincial court Thursday on charges of possession of stolen property. He remains in custody.
MacRae said another 200 items believed to be connected to the same case were found this week in Halifax, but he wouldn't elaborate.
He said the investigation began when officers pulled over a car last July and allegedly found a letter dated 1758 from British Gen. James Wolfe to his uncle in Dublin, apparently taken from Dalhousie University's archives years ago.
Dalhousie archivist Mike Moosberger said staff noticed the letter was missing after completing an inventory in 2009, but no one knew for sure whether it had been stolen or merely misplaced.
"It's certainly a relief to know it wasn't destroyed or isn't lost to the tides of time," he said. "We feel happy that at some point it will be returned to us and be part of the collection again."
Moosberger said anyone from the public is welcome to view items in the reading room of the archives, which is monitored by staff.
"Our primary mandate is to provide access to this material for historical research," he said.
"How this particular item was stolen, I can't say. But if a thief has it in mind to steal an item, there's always going to be an opportunity to do that."
MacRae said police have contacted a number of libraries, universities and small-town museums that are believed to be the rightful owners of the loot, including Mount Saint Vincent University in Halifax and Memorial University of Newfoundland.
One of the items recovered by police is an 1819 watercolour painting from Nova Scotia's legislative library.
MacRae said not all the institutions even realized the precious items were missing from their vast collections until they were contacted by the RCMP.
"They're quite thankful because a lot of these items have a strong historic value and are important to people," he said.
MacRae said police will rely on social media and the public to help identify the owners of other artifacts, which he said appear to be in good shape.
Investigators are also looking into whether some items were sold, including what's believed to be a first edition of Charles Darwin's "The Origin of Species" to a dealer in New York.
"Certainly people will become in possession of these (items) for profit, but sometimes it becomes a collection for themselves," said MacRae.