Complex sentence: The popular Kings Parade, which emerged in the historically significant year of 1918, was an initiative of the Ateneo de Sevilla, and was organized by it every year since, and is a prominent landmark among the major festivals of the city.
Split into simpler sentences: The popular Kings Parade, which emerged in the historically significant year of 1918, was an initiative of the Ateneo de Sevilla. The parade has been organized by it every year since, and is a prominent landmark among the major festivals of the city.