Complex sentence: The movement of the "urnfield people" that considerably changed the ethnic and cultural makeup of Podunavlje and one part of the Balkans did not significantly affect the area of Glasinac culture of the late Bronze Age.
Split into simpler sentences: The movement of the "urnfield people" considerably altered the ethnic and cultural makeup of Podunavlje. However, this particular movement did not significantly affect the area inhabited by the Glasinac culture of the late Bronze Age.