The Day of Ashura takes place on September 20, 2018. This date marks the tenth day of Muharram in the Islamic calendar and the climax of the Remembrance of Muharram. The date on the Gregorian calendar varies from year to year, since the Gregorian calendar is a solar calendar, and the Islamic calendar is a lunar calendar. However, the Islamic date does not vary but is the 10th day in the first month of the Islamic calendar. This month is one of the four sacred months of the year, and held to be the second holiest month, following Ramadan. The Day of Ashura has become a national holiday in countries like Afghanistan, Bahrain, India, Iran, Iraq, Lebanon, and Pakistan.
To Shi'a Muslims the Day of Ashura marks the martyrdom of Husayn ibn Ali, and is part of the Mourning of Muharram. Shiite celebrations have traditionally included rituals which have been condemned by many religious authorities under the claim that such practices are wrong or unislamic. Sunni Muslims call the Day of Ashura more often The Day of Atonement. They celebrate the day on which the Israelites were freed from the Pharaoh of Egypt. As Moses fasted as gratitude for this liberation, Sunni Muslims fast, too, on this day.