Who was Gustav Tidland of Blue Earth County, Minnesota, or possibly New Ulm in Brown County? This excerpt is from "The History of the Welsh in Minnesota, Foreston and Lime Springs, Ia. Gathered by the Old Settlers." Edited by Revs. Thos. E. Hughes and David Edwards, and Messrs. Hugh G. Roberts and Thomas Hughes. 1895.
"(April 1857) - Next morning a company from this Eureka fort went to Swan Lake to confer with Chief Red Iron. David Dackins and Gustav Tidland, who could speak some Sioux, were sent to the village to interview the Indians, while the rest of the company halted at the edge of the timber. Red Iron gave the messengers full assurance of peace and friendship, and the company returned with their confidence in the redmen somewhat restored."
The full text is at http://www.estelnet.com/catalunya-cymru/catala/blue_07.htm