Part of the Muslim community will celebrate the birthday of the prophet Muhammed, according to tradition on 12th of Rabi’-ul-Awwal of the lunar calendar, which in 2006 falls on April 11 for Sunni and April 16 for Shia. While some believers see the Mawlid or Milad (Arabic has no written vowels) as a modern addition to Islam, the tradition found its origin in the 13th century, others will commemorate the birth of the ‘Arab Jesus’ extensively.
Little factual is known from primary sources about the birth of Muhammed. The first account of his birth is a biography of ibn Ishaq. Ibn Ishaq wrote his biography about one hundred years afterMuhammed’s death, and his work we only know through quotes of two other historians who lived another hundred years later. Ibn Ishaq wrote his biography under the auspicien of the Abassid caliph of Baghdad Mansur, therefor the biography may be regarded as a predominantly Sunni document.
– Wikipedia – Islam