Complex sentence: The designation'Southern' was adopted in 1901 and dropped from normal usage in 1964 on the break-up of the Federation of Rhodesia and Nyasaland, and Rhodesia became the name of the country until the creation of Zimbabwe Rhodesia in 1979.
Split into simpler sentences: The designation "Southern" was added in 1901 and dropped from normal usage in 1964 on the break-up of the Federation of Rhodesia and Nyasaland. "Rhodesia" then remained the name of the country until the creation of Zimbabwe Rhodesia in 1979.