Describe symbolism in Iberia: Spanish Travels and Reflections by James A. Michener

In the section titled, Tereul, the Christians attacked the town of Teruel to rid it of its Moorish inhabitants. King Alfonso was able to hold his men strong and be victorious over the Moors. During their celebration, the Christians saw a symbol of their triumph. One bull survived the stampede the Moors released on them and remained on the crest of the hill, shaking its head up towards the sky. The Christians shouted "he has been converted to our side!" and that site became the official site of Teruel.