Pamplona’s devotion to San Fermín developed in the Middle Ages, with a relic arriving from Amiens in 1186. The municipal tourism history distinguishes religious tradition from claims about the saint’s life, whose historical details remain debated. By the end of the 16th century the feast had moved from October to July, meeting the season of livestock markets and creating the conditions for a broader popular celebration.

The bull runs grew from the practical movement of animals through the streets to the place of bullfighting. Music, neighbourhood clubs, giants and ceremonies developed alongside those events. Ernest Hemingway’s The Sun Also Rises, published in 1926, helped spread San Fermín’s international reputation. The modern fiesta remains both a local civic gathering and a major visitor event, with the procession of 7 July anchoring its religious identity.