A Johnson Called Thong

Hi, my name is Patty Johnson-Harrington. My Great-great grandfather Gustaf Johnson lived in the Acton area during the time of the Dakota wars. He was married to Johanna Hakanson in about 1860. He immigrated from Sweden in 1854 with his parents (who both died of cholera before actually making a home in Minnesota) and his siblings Elias, Johannes, Johanna, and Maja Lena. His brother Nicklaus immigrated the year before them.  I was told an interesting story by my uncle years ago, but have never found any conclusive evidence of it. I'm wondering what you think. His parents were named Jonas Johanson and Kajsa Inga Erhengisseldotter. They also used the Surname Thong, Tung or Tang. The story I was told is that Gustaf and his family (although uncle Bob did not know the names) were early pioneers from Sweden. They were living in a small community and that Gustaf's wife, Johanna was a kind of midwife who helped with birthing babies within the community and also with the Native American women nearby. The family was said to be friendly with some of the Natives and traded with them, as did most others there. Well, there was also alot of tension building as the Native Americans were being pushed further off their land and one morning the family found a mark or symbol painted on the door to their cabin. Gustaf asked an Indian he knew what the meaning of it was and he was told it was a warning and that they should leave town. They took it seriously and did leave. When they returned days or weeks later, all of the cabins in the entire settlement had been burned down except for theirs. The other members of the settlement saw them as Indian sympathizers and shunned them. So they adopted the name Thong (a name they used in the past while in Sweden, as it was not uncommon for a man to take on an additional name during their time in the military as was the case with Jonas ) and moved in with Maja Lena and her husband John Smith in Chisago county.  At the same time in Gustaf's military records for the Civil War he is listed as Thong and in the notes section it indicates he " was driven from the frontier by Indians", so I think there is a grain of truth. The family later returned to Kandiyohi county with the name Johnson again. It was that story that compelled me to start researching, but I haven't found any evidence of it. Let me know what you think. Thanks, Patty Harrington