Mont. Code Ann. § 70-28-103

All actions brought under 70-28-101 must be brought in the county in which the real estate or a portion thereof, as to which the title is sought to be quieted, is situated; provided that if the real estate is situated in more than one county, said action may be brought and prosecuted in either of said counties, and a transcript of the original judgment certified by the clerk of court shall be filed in the office of the clerk of court in the county other than which the action was brought in which any of the real estate affected thereby is situated.