No one is sure why the heart symbolizes love, but the Catholic Church contends that it became symbolic in 17th century when Saint Margaret Mary Alocoque created the Sacred Heart of Jesus, and the shape became associated with love and devotion. Valentine's Day greetings started many centuries ago starting in the Middle Ages, and the first written Valentine’s Day love connection happened in 1382 when Chaucer wrote about the first anniversary of King Richard II of England and Anne of Bohemia’s engagement: For this was Saint Valentine’s day when every bird of every kind that men can imagine comes to this place to choose his mate. A holiday custom progress bar for YouTube with Valentine's Day Heart Beating.