According to research by Beloit College archaeologists, the animal-shaped mounds, which date as far back as 700 A.D., can be traced to ancestors of the Ho-Chunk.
“There are a lot of gaps in our knowledge, but we're using two lines of evidence that seem fairly reliable right now. And it's on that basis that most people assert that connection between the effigy mounds and Ho-Chunk ancestors,” said Dr. Robert Salzer, a former Beloit College anthropology professor and one of the archaeologists conducting ongoing research related to the effigy mounds.
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Members of the Chippewa tribe recognize the validity of the Ho-Chunk's historical connections to the Beloit area as well, but are quick to point out the Ho-Chunk is not the only tribe that can prove a connection. U.S. government documents indicate the region around modern-day Beloit was shared by a number of tribes, including the Chippewa.
Just reading this, the data don't look all that strong to link any particular tribe. But it seems fairly given that a number of "tribes" shared the area in the past.