Pope John XII reigned from December 16, 955, to May 14, 964.
Pope Leo VIII (963-64) followed Pope John XII.
Pope John XII was born in 937.
Pope John XXIII followed Venerable Pius XII.
In 1968, Pope Paul VI was head of the Catholic Church.
Pope Pius XII was pope from 1939 to 1958.
If by "leader" you mean "the pope," then the leader of the Catholic Church in 1958 was either Pope Pius XII, who's reign ended in that year, or Pope John XXIII, who succeeded Pope Pius XII in that same year.
Pope John XII died on 964-05-14.
Pope John XII reigned from December 16, 955 until May 14, 964.
It was Pius XII. He was pope from Mar. 2, 1939 to his death on Oct. 9, 1958.
Pope John XII rewarded Otto I By Crowning Him Emperor of The Romans.
Pope Pius XII Pope John XXIII Pope Paul VI Pope John Paul I Pope John Paul II Pope Benedict XVI Pope Francis
Pope John XXIII, Antonio Cardinal Roncalli, was elected to the papacy following Pope Pius XII.