Complex sentence: St. Francis in the spring of 1213 met the Count Orlando of Chiusi della Verna, who, impressed by his preaching, made a gift of La Verna to him and his followers.
Split into simpler sentences: St. Francis in the spring of 1213 met the Count Orlando of Chiusi della Verna, who, impressed by his preaching. He made a gift of La Verna to him and his followers.