21 Ramadan

21 Ramadan is the twenty-first day of the ninth month of the Islamic calendar.
In the Lunar Hijri calendar, this day is the 257th day of the year.

Deaths

40 AH – Ali ibn Abi Talib, the first Imam of Shiites and the fourth Caliph of Sunnis
726 AH - Osman I, the founder of the Ottoman dynasty
1104 AH - Al-Hurr al-Amili, a Shia scholar and Faqih, author of Wasa'il al-Shia
1028 AH - Seyyed Majed Hosseini Bahrani, a Shia scholar, Faqih and poet
Moses - Prophet of the Israelites
Joshua - Moses' assistant and his successor
Events
40 AH - The beginning of the caliphate of Hasan ibn Ali, the older son of Ali and Fatimah, and a grandson of the Islamic prophet Muhammad, the second Shi'i Imam
40 AH - The allegiance of the people of Kufa to Hasan ibn Ali for the caliphate
40 AH - Retribution of Abd al-Rahman ibn Muljam, the killer of Ali
The day of the revelation of the Quran, holy book of Islam
Holidays and observances
The second Qadr Night of Ramadan according to Shiites, holding an official nightlife worship ceremony called Ehya night in Iran
Day of martyrdom of Imam Ali, an official holiday in Iran