Complex sentence: In 1913 Bellanca would be crucial to bringing in strong support from Italian workers during the 1913 New York Garment workers Strike, and concentrated his efforts at preventing Italian scabs from crossing the picket line.
Split into simpler sentences: In 1913 Bellanca was crucial in bringing strong support from Italian workers during the 1913 New York Garment workers strike. He concentrated his efforts on preventing Italian scabs from crossing the picket line.