It’s actually a cross between a golden retriever and a Chesapeake. This dog looks a lot like what I imagine a Tweed water spaniel looked like.
Remember that the Tweed water spaniel is an ancestor of several retriever breeds. I don’t think it is accurately called a water spaniel, for many descriptions of it suggest that it was more like a red, liver, or yellow St. John’s water dog. My reading of their exact conformation is much more like a curly-coated retriever but of a different color and with a less tightly curled coat. For that reason, I call it a Tweed water dog.
Check out the photos:
This painting is said to be a Tweed water dog. It looks very similar to the dog in the photos, except for the tail, which does look a like that of an Irish water spaniel.
Here’s another painting that points to what a Tweed water dog might have looked like.
The first litter of proto-golden retrievers born at Guisachan came from crossing a heavily-built way-coat named Nous with a Tweed water dog named Belle. We have a photo of Nous, but we have no idea what Belle looked like. However, form this painting of one of their female offspring, we can see that Belle was likely of a pale yellow coloration. She may have had brown skin and looked something like a deadgrass Chessie. It is very likely that the medium and lighter colors in golden retrievers (and maybe yellow flat-coats and yellow Labradors) come from this breed.