Juliana, the mother of the current queen of The Netherlands (Beatrix), had a basenji, Sarah. Probably a gift from her husband Bernhard, who was a real aficionado of all things African. I found a few pictures on the web. I believe it's the 60's and 70's.
Fula Nzara of the Congo was sired by Fulaflyaway of the Congo and my dogs are related through him. Queen Juliana was a patron of our club - the Basenji Owners and Breeders Association. It was wonderful to see the pictures, thank you for posting them.