four more days of fighting. Conquest of Soconusco and Guatemala Cortés despatched Pedro de Alvarado to invade Guatemala with 180 cavalry, 300 infantry, crossbows, muskets, 4 cannons, large amounts of ammunition and gunpowder, and thousands of allied Mexican warriors. Pedro de Alvarado passed through Soconusco with a sizeable force in 1523, en route to conquer Guatemala. Alvarado's army included hardened veterans of the conquest of the Aztecs, and included cavalry and artillery; there were also a great many indigenous allies from Cholula, Tenochtitlan, Texcoco, Tlaxcala, and Xochimilco. Alvarado was received in peace in Soconusco, and the inhabitants swore allegiance to the Spanish Crown. They reported that neighbouring groups in Guatemala were attacking them because of their friendly outlook towards the Spanish. Alvarado's letter to Hernán Cortés describing his passage through Soconusco is lost, and knowledge of events there come from the account of Bernal Díaz del Castillo, who was not present, but related the report of Gonzalo de Alvarado. By 1524, Soconusco had been completely pacified by Alvarado and his forces. Pedro de Alvarado and his army advanced along the Pacific coast unopposed until they reached the Samalá River in western Guatemala. This region formed a part of the K'iche' kingdom, and a K'iche' army tried unsuccessfully to prevent the Spanish from crossing the river. Once across, the conquistadors ransacked nearby settlements in an effort to terrorise the K'iche'. On 8 February 1524 Alvarado's army fought a battle at Xetulul, called Zapotitlán by his Mexican allies (modern San Francisco Zapotitlán). Although suffering many injuries inflicted by defending K'iche' archers, the Spanish and their allies stormed the town and set up camp in the marketplace. Alvarado then turned to head upriver into the Sierra Madre mountains towards the K'iche' heartlands, crossing the pass into the fertile valley of Quetzaltenango. On 12 February 1524 Alvarado's Mexican allies were ambushed in the pass and driven back by K'iche' warriors but the Spanish cavalry charge that followed was a shock for the K'iche', who had never before seen horses. The cavalry scattered the K'iche' and the army crossed to the city of Xelaju (modern Quetzaltenango) only to find it deserted. Almost a week later, on 18 February 1524, a K'iche' army confronted the Spanish army in the Quetzaltenango valley and were comprehensively defeated; many K'iche' nobles were among the dead. This battle exhausted the K'iche' militarily and they asked for peace and offered tribute,