Sunni Muslims celebrate Eid al-Mawlid an-Nabawī, the birth of the Prophet Mohammed which occurs on the 12th day of Rabi’ al-awwal, the third month of the Islamic calendar. 

This year, the day falls on January 3 in places such as the United States, and on January 4, in places such as Pakistan.

The majority of Shia Muslim scholars believe however that the Prophet’s birthday is on the 17th day of Rabi’ al-awwal. To solve this problem, Iran has in the past organized an Islamic Unity Week which combines both perspectives.