Ali ibn Abi Talib (AS) was the true successor of prophet Muhammad (p.b.u.h) after his death.

Prophet Muhammad (pbuh) did specify a successor before he died, however some companions of prophet (Sahaba) betrayed him and made Abubakr as his successor. I'm going to talk about the day in which Muhammad (pbuh) specified Ali as his successor. The Prophet traveled from Madina to Mecca to perform the pilgrimage there. It was in the tenth year of Hijra (ten years after his migration). News of his journey had reached the ears of the Muslims located in various locations. In order to be in the company of the Prophet and perform the rituals of the pilgrimage along with the Prophet, many groups and classes of people had gathered in Mecca. The Prophet completing the pilgrimage delivered several speeches among the crowds. He then decided to return to Madina. The crowds continued to accompany the Prophet. On his journey back the Prophet reached the hilly spot of Jahfa in the desert, also known as Ghadeer Khum. It was here that the Angel of Revelation, Gabreil, descended upon the Prophet with this verse of the Holy Quran (5:67): "Oh, Messenger. Proclaim what descended to you from your Lord; and if you do not so, you have not proclaimed His message. And Allah protects you from the people. Indeed, Allah does not guide the disbelieving people" The verse shows the importance of the issue which prophet should tell people and if Muhammad (pbuh) doesn"t proclaim it, he has not proclaimed Allah"s message. It"s the last days of prophet"s life and such an important issue showed be told to people. The verse also shows that if he proclaims that issue his life will be in danger! And some people who claim that they are Muslims (but in fact they were Kafir and had attended pilgrimage. Read Quran 2:34 it will give you the same impression) will threaten prophet's life! The event of Ghadeer shows us that the Prophet's life was soon to end, because he lived for only seventy days thereafter. On the other hand there was no Divine decree or commandment that the Prophet did not proclaim to the people. Hence, it is quite evident from this verse that the issue of succession to him is the point. The Prophet acted accordingly, then and there. After the noon prayers, he gave the order to have a pulpit made which was done so by heaping the camel"s saddles on top of each other. Everyone gathered around this pulpit. According to historians thousands of people were in that gathering (including Abubakr and Omar ibn Khattab). The Prophet went on the pulpit. The people were all too anxious to know the importance and the magnitude of the reason to as why the Prophet had stopped in that heat of the desert to speak. Not allowing him to postpone it to be made in the ease and the comfort of a town. Every indication was to show that the matter was of great importance. The Prophet predicted the nearness of his death, which he had also said in Mecca too. Then he spoke of his being the Prophet and that of his having acted upon the will of God in announcing the revelations to them and that he had to announce this last issue in completion of the religion. After these words he called Ali Bin Abi Taleb. Ali went next to him on the pulpit. The Prophet then took his hand and lifted it above his head so that as historians say, the whiteness of their armpits showed. There in the hot searing desert, holding Ali"s hand high above his head, automatically stopping all passing caravans, the Holy Prophet's voice rang out; "To whomsoever I was the guardian, Ali to be his guardian=Man kunto mawlah fahaza Ali'o mawlah" Then the Prophet blessed those who would help Ali and cursed those who would refrain from helping him." Allameh Amini in his book [1] brings you many references of Ghadeer day and happening. That book is among the top books written by Shia scholars. He devoted his whole life to write that book and has gathered Sunni Muslims' references. You will also find useful information about Ghadeer in [2]. The historians who had mentioned Ghadeer happening in their books can also be found in [3]. You can also find famous "Muhaddithin" who quote Hadith and religious sayings in [4]. They have talked about Ghadeer. Sunni brothers believe that our prophet (pbuh) didn't specify any successors. It's not logical that we think he left his Ummah (the group of Muslims) without a leader. Do they regard Abubakr wiser than Muhammad (pbuh)?!!! Because Abubakr specified Omar as his own successor. Abubakr knew that there should be a leader after his death but Muhammad (pbuh) didn"t know?! In this round I proved that our prophet Muhammad (pbuh) specified Ali as his successor in Ghadeer Khum. Thanks. Refrences [1] Al-Ghadir by Allameh Amini. [2]http://www.shiasite.org... [3] Here are the historians: "Bilazari in Ansab Al-ashraf "Ibn Qutaybah in Al-Imama wa al-Siyasa "Tabari in his book "Egyptian Ibn zulagh "Khateeb Baghdadi And many other historians. You will find 24 historians in Allameh Amini's book. [4] Here are Muhaddithin "Imam Shafi'i (A Sunni scholar)- Abu 'Abdullah Muhammad ibn Idriss- al nahaya of ibn athir "Imam Hanbali (A Sunni scholar)- Ahmad ibn Hanbal-Musnad and Managheb. And many other Muhaddithin