While there are theories about their ancestry, the Chesapeake Bay Retriever's lineage is considered to be:
* The "Chesapeake": A group of dogs brought to Maryland in the 18th century, possibly by a shipwrecked English vessel. These dogs were likely a mix of various breeds, including Newfoundlands, Irish Water Spaniels, and possibly some English Pointers.
* The "Bay Dog": A smaller, more agile dog native to the Chesapeake Bay region. These dogs were used by watermen for retrieving waterfowl.
Over time, these two groups were bred together, eventually leading to the development of the Chesapeake Bay Retriever we know today.