Original: When it was first proposed in 1956, in "The Prehistory of Eastern Europe, Part 1", Marija Gimbutas's contribution to the search for Indo-European origins was a pioneering interdisciplinary synthesis of archaeology and linguistics.
Simplified: When it was first suggested in 1956, Marija Gimbutas's answer to the question of Indo-European origins was a pioneering interdisciplinary synthesis of archaeology and linguistics.