Answer
In his pursuit of knowledge, Longfellow embarked on a European sojourn, expanding his intellectual horizons. During this period, he sought out academic centers of repute in prestigious institutions like the University of Göttingen, the Sorbonne in Paris, and the University of Madrid. Through these enriching experiences, Longfellow diligently delved into the realms of literature, languages, and history, gaining a profound understanding that would later inspire his literary masterpieces.