The most important communal event of the year for most Tijānī groups is the "Mawlid an-nabawī" (known in Wolof as the "Gàmmu," spelled "Gamou" in French), or the celebration of the birth of Muḥammad, which falls on the night of the 12th of the Islamic month of Rabīʿ al-'Awwal (which means the night before the 12th, as Islamic dates start at sundown and not at midnight).