Property of a Gentleman, Peder Severin Krøyer’s Anna Ancher and Marie Krøyer on the Beach at Skagen. Estimate: £150,000–250,000. To be offered for sale on 20 November at Sotheby’s, London.

LONDON - In the Michael and Anna Ancher House on the Northern tip of Jutland hangs a work by Michael Ancher, the significance of which has only recently come to light.

It is a copy of a painting by his friend Peder Severin Krøyer. Krøyer completed several preparatory oils for his 1893 ‘blue period’ masterpiece, Summer Evening on Skagen’s South Beach now in the Skagen Museum. It captures their wives, Anna Ancher and Marie Krøyer, walking on Skagen's South Beach. We know that following the work’s rapturous public reception, Ancher borrowed a version of the painting from his friend and secretly copied it, as he confessed his feelings of guilt in a letter to Krøyer.

Peder Severin Krøyer, Summer Evening on Skagen's South Beach, 1893 now in the Skagens Museum, Skagen (the final large scale version).

Krøyer was typically generous about the incident. But which of Krøyer's oils had Ancher actually copied? Not the finished large scale canvas, as this was quickly acquired by the opera singer Lilli Lehman in 1895. Nor the two similar, but much smaller, landscape studies, as they were markedly different in composition and both went directly into private collections.  

Peder Severin Krøyer, Summer Evening at the South Beach, Skagen. Anna Ancher and Marie Krøyer, 1893 in The Hirschsprung Collection, Copenhagen (one of the two smaller landscape studies).

It has long been assumed that he must have copied a study, currently in a British private collection. Yet there are distinct differences between the two works, in particular the painting by Krøyer is notably bigger and more rectangular than Ancher's copy.

Peder Severin Krøyer, Anna Ancher and Marie Krøyer on the Beach at Skagen, 1893, (54 by 60cm), Private Collection, UK.

So it was with some excitement that I examined a painting purportedly by Krøyer earlier this year with my colleague Claude Piening. Unsigned, unlined and dirty, there were many clues that it was by the hand of Krøyer: style and brushstroke; the characteristic palette; the simple stretcher; the Danish-style frame; a provenance unbroken since 1905; its listing in a book from 1923 cataloguing all known Krøyers, and labels on the reverse that refer to exhibitions that Krøyer participated in in the early 1900s.

However, even more convincing was its striking similarity to Ancher’s work in the Michael and Anna Ancher House. The two paintings share the same square format and dimensions, and from the foreground footprints in the sand, to the lapping of the water on the beach, and the slight hesitancy in the definition of the sash glimpsed to the side of the left hand figure, they are virtually identical.

Michael Ancher, Anna Ancher and Marie Krøyer on an Evening Walk on South Beach, 1897, in the Michael and Anna Ancher House, Skagen (Ancher’s copy of the painting by Krøyer that is being offered for sale in London on 20 November).

Given the extraordinary similarity between the two works, Ancher’s guilty confession is understandable. But perhaps it would have put his mind at rest to know that 115 years later it is his clandestine copy that has led us to rediscover Krøyer's original painting, which will be offered in our sale of 19th Century European Paintings on 20 November in London.