The Siege of Acre took place in May 1104. It was of great importance for the consolidation of the Kingdom of Jerusalem, which had been founded only a few years earlier. With the help of a Genoese fleet, King Baldwin I forced the surrender of the important port city after a siege that lasted only twenty days. Although all defenders and residents wishing to leave the city had been assured by the king that they would be free to leave, taking their chattels with them, many of them had been massacred by the Genoese as they left the city. Moreover, the attackers had also sacked the city itself.

Soon after its conquest, Acre became the main trading center and main port of the Kingdom of Jerusalem, in which it can transport merchandise from Damascus to the West. With Acre being heavily fortified, the kingdom now had a safe harbor in all weathers. Although Jaffa was much closer to Jerusalem, it was only an open roadstead and too shallow for large ships. Passengers and cargo could only be brought ashore or unloaded there with the help of small ferry boats, which was a particularly dangerous undertaking in stormy seas. Although Haifa's roadstead was deeper and protected from south and west winds by Mount Carmel, it was particularly exposed to north winds.