King Henry II of England died on 6 July 1189 after a surprise attack by his son Richard the Lionheart and King Philip II. Richard inherited the crown and immediately began raising funds for the crusade. In the meantime, some of his subjects departed in multiple waves by sea. Some of them together with contingents from the Holy Roman Empire and France conquered the Moorish city of Silves in Iberia during the summer of 1189, before continuing to the Holy Land. In April 1190, King Richard's fleet departed from Dartmouth under the command of Richard de Camville and Robert de Sablé on their way to meet their king in Marseille. Parts of this fleet helped the Portuguese monarch Sancho I defeat an Almohad counterattack against Santarém and Torres Novas, while another group ransacked Christian Lisbon, only to be routed by the Portuguese monarch. Richard and Philip II met in France at Vézelay and set out together on 4 July 1190 as far as Lyon where they parted after agreeing to meet in Sicily; Richard with his retinue, said to number 800, marched to Marseille and Philip to Genoa. Richard arrived in Marseille and found that his fleet had not arrived; he quickly tired of waiting for them and hiring ships, left for Sicily on 7 August, visiting several places in Italy en route and arrived in Messina on 23 September. Meanwhile, the English fleet eventually arrived in Marseille on 22 August, and finding that Richard had gone, sailed directly to Messina, arriving before him on 14 September. Philip had hired a Genoese fleet to transport his army, which consisted of 650 knights, 1,300 horses, and 1,300 squires to the Holy Land by way of Sicily.
Question: France conquered the Moorish city of Silves in Iberia how many years before King Richard's fleet departed from Dartmouth?
Answer: 1