Complex sentence: In 1952, the "North Territory of Baja California" became the 29th state of Mexico as Baja California, and in 1974, the "South Territory of Baja California" became the 31st state as Baja California Sur.
Split into simpler sentences: In 1952, the "North Territory of Baja California" became the 29th State of Mexico as Baja California. In 1974, the "South Territory of Baja California" became the 31st state as Baja California Sur.