Complex sentence: Men from all over Greece compete for the honor of joining Jason; men who, because their ship is named the "Argo" after her builder Argus (Laurence Naismith), are dubbed the Argonauts.
Split into simpler sentences: Men from all over Greece compete for the honor of joining Jason. Because their ship is named the "Argo" after her builder Argus (Laurence Naismith), the crew are dubbed the Argonauts.