According to the date, the property was not yet a part of the United States - it was still "wild." A treaty had been signed by the government promising to stay off the property, so technically they could not be called settlers.
Would you accept someone "settling" on your front yard - or kicking you out altogether?
Couldn't really call them "miners" because they weren't professionals sent out to do a job. They were just going through people's homes and destroying property in the hopes of making a fortune.