Complex sentence: In earlier time periods Byelorussian territory was commonly referred to in Western Europe as White Russia ("Byelo Russia " literally meaning"White Russia"), and therefore the republic was sometimes known during its early existence as the White Russian Soviet Socialist Republic.
Split into simpler sentences: In earlier time periods, Western Europeans frequently referred to Byelorussian territory as White Russia ("Byelo Russia " literally means"White Russia"). During its early years in the USSR, the republic was sometimes known as the White Russian Soviet Socialist Republic.