As a result of rejecting the priesthood in the spirit world, some were not allowed to have the priesthood during their earth life. This restriction lasted from generation to generation. However from earliest times it was promised that some day this ban or restriction would be lifted so that righteous men throughout the world could receive the priesthood.
This glorious promise was fulfilled on June 1, 1978 when Spencer W. Kimball -- the prophet of the Lord at that time -- was told by the Lord that henceforth all worthy males, regardless of race, would be allowed to receive the priesthood. When the revelation was presented to the body of General Authorities they all received a glorious confirmation that it was true. Since then, a tidal wave of missionary work has gone out into every nation tongue and people. Now men of all races are on the same standing as they were originally in the pre-existence.