To find out why, let's return to the Qur'an. The 106th surah, named after Muhammad's tribe, "The Quraysh," presents the nature of things before Islam. Qur'an 106:1 "For the protection of the Quraysh (there are covenants covering the journeys of trading) caravans (so that they can) travel safely by winter and summer. So let them worship the Lord of this House (the Ka'aba), (He) Who provides them with food and with security against fear and danger." This is a fairly accurate reflection of pre-Islamic Mecca, its caravans, covenants, protective months, and Ka'aba.