Eero Nelimarkka returned to his parents' birthplace at the end of the 1920's. He bought some land from Pekkola where he had his summer house built. Later he use to spend the summers at the Nelimarkka Residence.
Nelimarkka had already during the 1930's dreamed of establishing his own art school. During the 1960's his financial situation allowed him to ful fil this dream. Professor Aune Lindström gave him the idea of connecting a museum to the art school.
Eero Nelimarkka asked his friend, architect Hilding Ekelund, to draw plans for the combined art school/museum building, who had promised already 30 years ago to do such plans for this type of house. The exterior of the building shows influence of classical architecture. To the basement Ekelund designed studios for painting and sculpting purposes, but they were never used for their original purpose, although Nelimarkka did hold some courses for painting.
Soon the building was found to be too small, and since Ekelund was not well to do more plans, Nelimarkka designed the extension to the building himself. The museum was extended twice during 1972-73. During the years 1996-97 the building was once again extended according to the plans made by the architects Simo and Käpy Paavilainen, who had also planned the primary repairs to the building in 1980's.
Eero Nelimarkka himself kept the museum open, up until nearly to the time of his death. He used to come and greet visitors, wearing his white painter's jacket, and chatting with people who came to the museum. As a productive artist, he also worked in the museum painting portraits or was studying the everchanging scenery from the kitchen window.
The Nelimarkka Museum was bought by Alajärvi Municipality at 1981. At 1995 it became a Regional Art Museum.