Fatima bt. al-Imam al-Husayn (a) was the eldest daughter of Imam al-Husayn (a) and her mother was Umm Ishaq. She was present in Karbala, and, according to a hadith from Imam al-Baqir (a), Imam al-Husayn (a) gave her the trusts of Imamate and his written will for safekeeping, and she later delivered them to Imam al-Sajjad (a).
Before the Tragedy of Karbala, Fatima married her cousin al-Hasan al-Muthanna, the son of Imam al-Hasan (a) Fatima was present in Karbala together with her husband, who was one of the injured in that incident. Together with the other members of Imam al-Husayn's (a) family, Fatima was taken to Kufa and then to Damascus as a captive. She is the narrator for some of tragic incidents in Karbala and afterwards. There was an exchange of words between her and Yazid at the latter's court. Ahmad b. Ali al-Tabrisi has recorded her debates with the people of Kufa. Zayd bin Moosa bin Ja'far relates from his father, who relates from his fathers the sermon of Fatemah Sughra (a.s.), which she delivered after returning from Karbala:
"Praise be to Allah equivalent to the particles of sand and the weight of the heavens until the earth. We praise Him and believe in Him and rely upon Him alone, and we say that there is no other Deity except Allah. He is Unique and has no associate, while Muhammad (S) is His Slave and Messenger. And the heads of his sons have been severed innocently on the banks of the Euphrates. O Allah! I seek refuge in You if I attribute falsehood to You, or if I misconstrue against what you ordered regarding the pledge of the Vicegerency of (Imam) Ali bin Abi Talib (a.s.), whose right was usurped. He was also innocently killed in one of the houses of Allah as they killed his sons yesterday. There was present a group of men who claimed to be Muslims, may their heads not remain upon their necks, he was thirsty until his soul was taken up to You. He was of a praiseworthy character, pious lineage, and renowned qualities and acclaimed Religion and he did not fear rebuke and reproach in Your Path.