Complex sentence: Sometime in the 1970s the Crime Syndiacte from Earth-3 traveled to Earth-2, the JSA (including Starman) and the JLA from Earth-1 banded together to defeat and imprison the Crime Syndicate in a dimensional barrier outside normal time/space.
Split into simpler sentences: Sometime in the 1970s the Crime Syndicate from Earth-3 traveled to Earth-2. The JSA (including Starman) and the JLA from Earth-1 banded together to defeat and imprison the Crime Syndicate in a dimensional barrier outside normal time/space.