Randolph M. Probstfield is commonly considered Clay County’s first European settler-colonist. A farmer in the Red River Valley, he was a local leader in politics, education, and agricultural development from his arrival in Minnesota in 1859 until his death in 1911.

Concerned by the anti-Japanese atmosphere in the United States in the 1920s, Dr. Sidney Gulick established the Committee on World Friendship Among Children and began sending friendship dolls to Japan. Japan reciprocated by sending friendship dolls to the US in 1927, with Minnesota receiving a doll known as "Miss Miyazaki."

South Dakota Hutterite families with roots in the Anabaptist Reformation of the sixteenth-century moved to Cottonwood County in 1994. There, they established the Neuhof Hutterian Brethren Colony and the Elmendorf Hutterian Brethren Colony south of Mountain Lake, Minnesota.

The Norwegians who made their homes along the Buffalo River in 1870 were among the first European settler-colonists to live in Clay County. The timing of their arrival, before the land had been surveyed, helped to draw other immigrants to the area.

The St. Paul Resettlement Committee formed in October of 1942 to assist with the relocation of Japanese Americans from the concentration camps established by the US government in March of 1942. It was one of thirty-five such committees that operated across the country during World War II.