Items found: Rare edition of Charles Darwin's On the Origin of Species.

1819 watercolour painting of N.S. Province House.

18th century letter written by Gen. James Wolfe before the Siege of Louisbourg.

Nova Scotia police say they have recovered hundreds of allegedly stolen items from a Fall River home that include rare first editions of books, one-of-a-kind documents and art taken from multiple collections.

A traffic stop last summer led police to search John Mark Tillmann's Fall River home, where they found more that 800 allegedly stolen artifacts that police estimate may be valued at more than $1 million.

Police pulled Tillmann over last summer for breaching the conditions of his house arrest. During that stop they found a few unusual items in the 51-year-old man's vehicle, including a letter written in 1758 by British military leader Gen. James Wolfe.

Wolfe was one of the British leaders who led an attack on the French during the Siege of Louisbourg in the 18th century, effectively ending the French colonial era in Atlantic Canada.

After months of investigating the letter, police finally tracked it to Dalhousie University. Once they confirmed it was a stolen antiquity, police obtained a search warrant for Tillmann's house and arrested him following the search.

Police began their search early Friday morning and continued their search on Tuesday, cataloging hundreds of items — anything that looked to be an antique or rare object.

One item of note seized appears to be a rare edition of Charles Darwin's pivotal scientific work, On the Origin of Species.

Police said they have tracked the owners of many artifacts already, and have confirmed theft or fraud.

RCMP Cpl. Scott MacRae said local police are working with the U.S. Federal Bureau of Investigation to track down leads on where some of the artifacts may have come from.

"We believe that items such as books, documents, paintings, antiques were stolen from private collectors around Atlantic Canada, also from local universities, museums and even the legislature," said MacRae.

A watercolour of N.S. Province House painted by John Woolford in 1819 was discovered. The painting is similar to this painting in the same series. (CBC)

"We believe we have a painting from the Nova Scotia legislature so as one can see, it's a vast undertaking."

On Monday, Tillmann was charged with being in possession of four rare antiquities taken from universities in Halifax, from the archives and from the Nova Scotia legislature.

Dalhousie Archivist Michael Moosberger told CBC News he estimates the Wolfe letter that began the investigation is worth nearly $18,000.

He said with the amount of items in the archives, it's possible for items to go missing. He said if all the boxes of material in the archives was lined up, it would stretch seven kilometers from end to end.

"Somebody could take a letter out and we might never be aware it went missing," he said.