Rudolf Koller (1828–1905) was a Swiss painter born and active in Zurich. He worked in a realist and classicist style, also associating with the romantic Düsseldorf school of painting.
Koller specialized in animal painting, particularly depicting cows within Swiss landscapes, which led to his description as "the painter of the Swiss national animal." His landscape works, often executed in the plein air tradition, include Swiss mountain scenes, exemplified by The Gotthardpost (1873), which depicts a mail coach drawn by white horses. His style aligns with realist painters such as Gustave Courbet and Jean-Baptiste-Camille Corot.
Koller is considered among the important Swiss painters of the 19th century, alongside Frank Buchser and Gustave Eugène Castan. His contributions to animal painting drew comparisons to artists like George Stubbs, Rosa Bonheur, and Théodore Géricault.
