In all cases prior to July 1, 1959, where patent has issued to the heirs of a decedent under the laws of the United States and the county court of the county wherein such patented land is situated has determined who were the heirs of such decedent and their respective shares in and to said patented land, such decrees of said county court establishing and declaring such heirship and such shares shall have the same force, effect, and validity as though made by the circuit court for said county.
SDCL 21-39-2