Complex sentence: In 1896 Barrymore became the first major Broadway star to headline in vaudeville--a brave foray at the time that he speculatively would have later made into motion pictures had he lived.
Split into simpler sentences: In 1896 Barrymore became the first major Broadway star to headline in vaudeville. A brave foray at the time that he specutively would've later made into motion pictures had he lived.