The poster, which was created by renowned artist John Gilroy in 1962, shows a group of animals – all of which had been used in previous Guinness advertising campaigns – crowded around a zoo keeper below the words: “See the Guinness Animals at Edinburgh Zoo”.
It is believed that the poster was one of two created as part of the Edinburgh Zoo campaign, while similar adverts were also used to help attract visitors to Dublin Zoo in Ireland.
The animals include a kangaroo, a bear, an ostrich and the Guinness toucan, which still features in marketing for the brand.
The poster is now up for sale for $1,700 (£1,320) after being unearthed by New York-based poster art collector Mickey Ross.
A spokesman for Diageo, which owns Guinness, said: “The Gilroy posters for Guinness are amongst the great classics of brand advertising. His animal posters were very popular and we know from our Guinness Archive that there was a poster linked to Edinburgh Zoo created in 1962.
“We don’t have any specific information about the links with Edinburgh Zoo, but we do know that around the same time the brand had a partnership with Dublin Zoo and that a similar poster was created inviting members of the public to see the Guinness animals in Dublin Zoo.”
According to the Guinness archives, all of the zoo animals appeared together for the first time in 1953 with a poster designed to commemorate the Queen’s coronation.
Gilroy, who also created posters for the Government’s Ministry of Information during the Second World War, as well as painting portraits of royalty and other well-known figures, began working for the London ad agency SH Benson in 1925.
He quickly became best known for his Guinness adverts featuring a zoo keeper – a caricature of himself – and animals enjoying the Irish drink with the slogan “My Goodness, My Guinness”. Gilroy was inspired to draw the animals after a trip to a local zoo, where he saw a sea lion balancing something on its nose – an image he re-created with a bottle of Guinness in one of his earliest posters.
Seller Mickey Ross, founder of the Ross Art Group, on New York’s Madison Avenue, said he bought the poster from a private collector of Guinness memorabilia in the UK late last year.
He said: “This whimsical poster really captures some of the fun and attraction of being at the zoo, but at the same time amuses the Guinness consumer.
“In the style of the Guinness advertising at the time, the poster also has a cheeky side to it, which is delightful.
“It isn’t often that we see a beer company in a joint marketing effort with a zoo.”
Edinburgh Zoo refused to comment.