The Birth of Bahá’u’lláh, founder of the Bahá’í Faith, is celebrated on one of the Twin Holy Birthdays, usually in October or November, based on the Bahá’í lunar calendar. Born in 1817 in Tehran, Iran, Bahá’u’lláh is honored for his teachings on unity, peace, and the oneness of humanity. The day is marked with joyful gatherings, prayers, music, and reflection on his life and message.