Banu Hashim (Arabic: بنو هاشم) was a clan within the tribe of Quraysh, and Prophet Muhammad was a part of this clan. The clan was named after the great-grandfather of the Prophet, Hashim ibn Abd Munaf and they are also referred to as Hashemites.
There were two tribal confederations in pre-Islamic Arabia; the Adnani who originated from Adnan who was from the off springs of Prophet Ismael. He was the traditional ancestor of the Arabs of northern, central and western Arabia, and the Qahtani who are the descendants of Ya'rab ibn Qahtan who was the traditional ancestor of the Arabs of southern and south eastern Arabia. The descendants of Adnan were sub-divided into many tribes. The tribe which acquired fame from amongst them was that of Quraysh and Bani Hashim formed a part of it.
Before the advent of Islam, Banu Hashim were not habituated to cunning and deceit and did not deceive the simple-minded people on the pretext of their religious and spiritual leadership. According to their code, helping the oppressed, sympathizing with the helpless, warding off injustice, and meeting the needs of the indigent, was compulsory. They did not deceive anyone and did not consider hypocrisy to be permissible. It was in this clan, that Prophet Muhammad (pbuh) was born and being a member of this clan of high prestige was one of the factors that saved him from assassination by the enemies.
Throughout history, rift had existed between Bani Hashim and the clan of Bani Umayyah - both clans traced their lineage back to Abd Munaf ibn Qusai. Before the advent of Islam, issues pertaining to superiority complexes, old grudges, desire for vengeance of the murder of kinsmen, political views, personal sentiments and mere differences in ways of life and manner of thinking caused conflicts between the two clans. After the advent of Islam, the Bani Umayyah had remained hostile for a long period of time as they wished that the predominance and authority of Bani Umayyah should not be affected due to the prophetic mission of Prophet Muhammad. During the reign of the third caliph Uthman ibn Affan, who was also an Umayyad, this rift started to become violent as the Umayyad Dynasty gradually moved into power and ruled for almost hundred years until they were defeated by the Abbasids.
In regards to the clan of Banu Hashim, the Prophet Muhammad (pbuh) has been quoted to have said: "Allah chose Ismail from the children of Ibrahim, and chose Kananah from the children of Ismail, and chose Quraysh from the children of Kananah, and chose Banu Hashim from Quraysh and then chose me from Banu Hashim." Today, the descendants of Prophet Muhammad carry their lines of descent from Imam Hasan ibn Ali and Imam Husain ibn Ali, born of the union of his daughter Fatima and his cousin Ali ibn Abu Talib. They usually carry the title of Sayed.