Complex sentence: The third hymn, also considered as an anthem, was "Jerusalem", whose words, based on the Romantic Era poem by William Blake, were set to music in 1916 by Sir Charles Hubert Hastings Parry.
Split into simpler sentences: The third hymn, also considered as an anthem, was "Jerusalem". Based on the Romantic Era poem by William Blake and set to music in 1916 by Sir Charles Hubert Hastings Parry.