Wilhelmina van Gogh (1862–1941), Dieren, The Netherlands 
by 1928 – still in 1952
Line Kruysse (1858–1937), wife of the late Jacob Herman (Koos) le Cosquino de Bussy (1848–1917), Amsterdam, The Netherlands; C. Kruysse, Amersfoort, The Netherlands, by inheritance 
by 1953/09 – 1954/10/20
E.J. Van Wisselingh & Co., Amsterdam, The Netherlands 
National Gallery of Canada, purchased from Van Wisselingh 
The main source for this provenance is J. B. de la Faille's catalogue raisonné, cat. no. 601 [de la Faille, J.B. "L'Oeuvre de Vincent van Gogh." Paris, 1928, 1970 ed. Meulenhoff, Amsterdam, cat. no. 601]. Exceptions and other supporting documents are noted.
 Wilhelmina van Gogh, also called Wil, is the artist's younger sister.
 Mme J. H. Le Cosquino de Bussy is mentioned as second owner of the painting in de la Failles catalogue raisonné of 1928 and also in the later edition of 1939 [de la Faille, J.B (see above), F 601 and de la Faille J.-B. “Vincent Van Gogh.” cat. raisonné, Paris: Hyperion, 1939, F601]. The Iris was on loan to the Museum Boymans, Rotterdam in 1937 [“Museum Boymans. Concise Catalogue. Paintings and Sculptures.” Rotterdam 1937, cat. no. 729]. Mme J. H. Le Cosquino de Bussy can be identified as Line Kruysse, second wife of Jacob Herman Le Cosquino de Bussy and a friend of Wilhelmina van Gogh [letter from Wilhelmina van Gogh to Line Kruysse, dated August 26, 1886, “Bulletin of het Van Gogh Museum” 1992/3, vol.7, excerpt posted on the Van Gogh Museum's website, “The Letters”, accessed July13, 2009 http://www.vggallery.com/index.html]. In 1952 the painting was included in an exhibition at the Redfern Gallery in London [“Some aspects of modern Dutch painting.” The Redfern Gallery, London, March 26–April 26, 1952, cat no. 9]. The catalogue mentions C. Kruysse, Amersfoort, as the owner. C. Kruysse most likely inherited the painting from Line Kruysse after her death in 1937 rather than acquiring it from Van Wisselingh, as suggested in de la Faille's catalogue raisonné.
 Van Wisselingh most likely purchased the painting from C. Kruysse. The Amsterdam art dealer first offered the painting to the NGC in September 1953 [Accession records, NGC curatorial file]. In the Van Wisselingh archive, the painting is listed under stock number S 1127 [Van Wisselingh archive, Rijksbureau voor Kunsthistorische Dokumentatie, The Hague, The Netherlands]. The stock book mentions only Wilhelmina van Gogh and J. H. le Cosquino de Bussy, Amsterdam, as former owners.
 Accession log [NGC curatorial file].