The siege of Silves was an action of the Third Crusade and the Portuguese Reconquista in 1189. The city of Silves in the Almohad Caliphate was besieged from 21 July until 3 September by the forces of Portugal and a group of crusaders from northern Europe on their way to the siege of Acre. The defenders capitulated on terms, the city was handed over to Portugal and the crusaders took a portion of the spoils.
The call for a new crusade went out in 1187, following the loss of Jerusalem. The first fleets from the north arrived in Portuguese waters in the spring of 1189. One of these sacked Alvor and massacred its inhabitants some weeks before the fleet that would attack Silves had assembled in Lisbon in early July. The combined Portuguese–crusader fleet contained 75 ships—37 cogs of the northern type and 38 galleys. It carried an army of 3,500 crusaders, while King Sancho I of Portugal marched overland with his own army.
The crusaders camped before Silves on 20 July and launched an assault with scaling ladders the following day. They successfully captured the walled lower town and began preparing siege engines. Sancho arrived on 29 July and his army a day later, at which point the city was completely surrounded. The assault with engines began on 6 August. Attempts to undermine the walls and towers began on 9 August and continued, with varied success, until the end. The defenders countermined and there was fighting underground, possibly including the use of Greek fire by the Almohads. On 10 August, the breastwork was captured. By mid-August, the defenders were suffering from a shortage of water. On 1 September, the Portuguese offered terms and the defenders agreed to negotiate. The crusaders refused to relinquish their right to plunder, but the defenders were permitted to leave in peace. On 3 September, the city was handed over to Sancho, who in turn permitted its occupation by the crusaders for dividing the booty. They eventually abandoned the city under pressure and, after establishing a garrison, Sancho left on 12 September.
The fall of Silves meant that nine outlying castles subject to its Almohad governor came under Portuguese control. In addition, Albufeira surrendered. The crusaders, however, refused to help besiege Faro and sailed away on 20 September to resume their crusade. The success at Silves was relatively short-lived. In April 1190, the Caliph Yaʿqūb al-Manṣūr launched an offensive intending to take back Silves. His first effort failed, but he renewed his invasion in April 1191 and Silves was recaptured in July.
Sources
The main source for the siege of Silves is an eyewitness account. The Narratio de itinere navali (Account of the Seaborne Journey) is a short but detailed Latin narrative of the crusader expedition from northern Germany told from a crusader's perspective. It was composed shortly after the capture of Silves, certainly before 1191. In the only manuscript of the text, it is accompanied by the Epistola de morte Friderici imperatoris (Letter on the Death of the Emperor Frederick), which demonstrates a connection between the naval expedition and Frederick Barbarossa's overland crusade.
The next most important source, the Ymagines Historiarum of the English chronicler Ralph of Diceto, is also in Latin and from a northern perspective. Also from England are the Gesta regis Henrici secundi and the Chronica of Roger of Howden that relies on it. There is confusion in some sources, such as the Itinerarium peregrinorum et gesta regis Ricardi and the Chronicon of Robert of Auxerre, between the sack of Alvor and the capture of Silves. Nevertheless, Robert's account made its way into the chronicle of William of Nangis, the Chronicon Turonense and a lost work by a certain Hugo, copied by into his Memorias Ecclesiasticas do Reino do Algarve. A supposed letter from Pope Clement III to the Byzantine emperor Isaac II is in reality a 16th-century forgery. Its reference to the conquest of Silves is derived from the confused account of Robert of Auxerre.
The only sources to originate in Portugal are the contemporary but terse Chronicon Conimbricense and the Crónica de 1419. The section of the latter devoted to the reign of Sancho I claims to be based on an earlier contemporary source, but is obviously reworked.
The most valuable Arabic sources for the loss of Silves are the Bayān al-mughrib of Ibn ʿIdhārī, specifically, its third book covering the Almohad period (1170–1266), and the Almohad history of ʿAbd al-Wāḥid al-Marrākushī. It is also mentioned in the works of Ibn al-Athīr, Ibn Khaldūn, Ibn Abī Zarʿ and al-Maqqarī.
Background Status of Silves Silves (Arabic Shilb or Xelb) lies on the Arade some upriver from the coast. It is sited on a hill high. The river was crossed at that point by a bridge. The city's population in 1189 was 15,800, according to the Narratio. It came under indirect Almohad rule in 1146, when it was captured from the Almoravids and placed under the rule of Ibn Qasī, leader of the local Murīdūn sect. It came under direct Almohad rule in 1157. It was the capital of the province of al-Gharb. Its governor in 1189 was ʿĪsā ibn Abī Ḥafṣ ibn ʿĀlī. According to Ibn ʿIdhārī, he was "very experienced in the defence of the frontiers."
As a place of strategic significance, the fortifications of Silves were extensive, but perhaps not "fully developed" in 1189. They had been sufficient to require siege engines during the siege of 1063. The Almohads had made repairs after taking full control in 1157. The hilltop was surrounded by a rampart of rammed earth faced with stone. It had at least seventeen towers of the albarrana type, that is, set outside the wall and connected to it by means of elevated walkways. The tower below the main gate was especially large. They were not hollow structures but rather elevated fighting platforms, solid to a height equal with the walls. Two parallel walls led down from the hilltop to the river, protecting the water supply, which was also protected by four towers. The author of the Narratio calls the walled section leading to the river a corrasce, from the local Romance word couraça, "breastwork". The suburb at the base of the hill had a weaker system of walls and was protected by a single tower. The fortifications are described in detail by al-Idrīsī.
Despite his experience, Ibn Abī Ḥafṣ had not properly prepared supplies for an extended siege. There had been a drought, which left the water in the harbour of Silves so low that five galleys—vessels of low draught—were stuck there. In addition to shortages of food and water, there was a shortage of armour and soldiers. Four hundred Christian prisoners had to be dragooned into service.
Portuguese planning In October 1187, Jerusalem was captured by the Ayyubids and Pope Gregory VIII issued a call for a new crusade to recover it in his bull Audita tremendi. King Sancho sent a letter to Gregory, which was misinterpreted in later tradition as showing an intention to join the planned crusade. Although Sancho probably did not intend to go on crusade, he did perceive the value of crusaders sailing to Portugal on their way east. Such a fleet had assisted in the conquest of Lisbon in 1147 during the Second Crusade.
The first crusader fleet to arrive consisted of fifty to sixty ships from Denmark and Frisia. They arrived in June 1189. At Sancho's invitation, they helped take Alvor. Contrary to conventions, they massacred its inhabitants. As soon as they had taken their share of the plunder, they sailed on. Sancho and his forces to return to Lisbon to await the next group of crusaders.
Crusaders' voyage (April–July)
In April 1189, a fleet of eleven ships of crusaders bound for the Holy Land left Bremen. The author of the Narratio was on one of these ships. He records that composition of the crusader company was variable, as some joined up at a later point in the voyage while others left to find their own way to the Holy Land. They seem mostly to have come from the north of the kingdom of Germany in the Holy Roman Empire, since the author of the Narratio refers to these as "our kingdom" and "our empire".
The fleet entered the sea at at the mouth of the Weser on 22 April. One ship was left on a sandbank on 23 April, to rejoin the fleet later. The rest arrived at Lowestoft in England on 24 April. On 25 April, three ships ran aground on sandbanks while the fleet was trying to enter the port of Sandwich during a storm. No men were lost and the equipment was saved, but only one ship could be salvaged. Repairs took 23 days, from 26 April to 18 May.
After purchasing one replacement ship in London, the fleet left Sandwich on 19 May and sailed west along the coast of England to Winchelsea, Yarmouth (23 May) and Dartmouth (24 May). Some men of London which the Gesta regis Henrici secundi records as present at the fall of Silves may have joined the fleet at this time. The fleet sailed for Brittany on 25 May and were at sea six days before landing on Belle Île, where they spent eight days waiting for winds. Rounding Brittany, they put in for one day at La Rochelle (9 June). They then sailed across the Bay of Biscay to the Bay of Luanco by the castle of Gozón in the kingdom of León, where they arrived on 18 June.
On 19–20 June, the crusaders made a brief pilgrimage overland to Oviedo Cathedral. They sailed from Luanco on the morning of 22 June and arrived at the mouth of the Tambre, either in Muros or Noia, late on 23 June. Some went overland on a pilgrimage to Santiago de Compostela. A galley from Tui joined the fleet in Galicia, bringing its size back up to eleven ships, although not the same eleven it had started with. The augmented fleet set out on 1 July and arrived in Lisbon on 3 or 4 July.
Campaign (July–September) Preparations and manoeuvres
At Lisbon, the crusaders learned of the sack of Alvor and were invited to take part in an attack on Silves. Depending on the reading of the Narratio, Sancho made this request either while he was preparing his expedition or else after he had begun his march. According to the agreement as presented in Ralph of Diceto, the king agreed to let the crusaders keep any booty they took if they recognized his right to the city.
There were at that time either 24 or 44 other ships in the harbour of Lisbon. Some of these may have been a part of the fleet of 37 English crusader ships that, according to Ralph, left Dartmouth on 18 May and arrived in Lisbon on 29 June. According to the Narratio, the crusader fleet—which now numbered 36 "great ships" (cogs) and the one Galician galley—remained at Lisbon for eleven days. The Crónica de 1419 says that the crusaders were accompanied by 36 priests, which tallies well with the claim in De expugnatione Lyxbonensi that the 1147 fleet that conquered Lisbon carried one priest per ship.
On the evening of 14 July, the fleet sailed from Lisbon for Silves. According to Ralph, Sancho contributed a fleet of 37 galleys plus a large number of pinnaces. Ralph and the Narratio put the strength of the crusader army at 3,500 men, which is generally accepted as accurate. Those that sailed from Blexen seem mostly to have been commoners. In the entire Narratio, the only nobleman mentioned among the crusaders was a Galician knight who had come aboard as a pilot.