Who was the first person the prophet Muhammed called to Islam?

In a Nutshell: The Prophet (saw) firstly did not non-influential individual (person), he rather called the either tribe's members collectively or the tribal leaders. The earlier companions (ra) heard such rumours and would approach the Prophet (saw) and he would tell them of revelation and conversions subsequently would happen. These companions (ra) in turn would tell others and bring them to the prophet (saw) and so on. Introduction When the Prophet (saw) first received revelation, he was not asked to call people to the Islam as individuals. The revelation was for his nation, community or polity so that they would reorient their collective way of life - changing their structures, laws, culture, traditions and norms. After being commanded to do so, he would focus on the tribal elites and leaders, those whom society trusted and would follow - as opposed to individuals who would personally agree with him whilst society still continued with their existing way of life ie missionaryism. It does not mean he neglected or rejected non-influential individuals, as any who heard of his call, he invited them to believe in him and the truth he bought, teaching it to them. Rather he proactively focused on influentials and leaders who could more easily ensure a transition to a new way of life along with their followers who trusted them. The first to receive the dawa When revelation began, Allah ordered his Prophet (saw) to start calling people to Islam, starting with his clan and the families within it. Allah says: وَأَنذِرْ عَشِيرَتَكَ الْأَقْرَبِينَ   "And warn, (O Muhammad), your closest kindred." (Qur'an 26:214) The Prophet (saw) asked Ali (ra) to prepare a banquet and invite the leaders of his clan (Banu Abd al-Muttalib). Ali cooked the meal and invited about forty men of the leaders. The men then left before the Prophet could speak with them. He invited them again and after the meal he proclaimed:  ِيا بَنِي عَبْدِ المُطَلِبْ، إنِي والله ما أَعْلَمُ شَابًا فِي العَرَبِ جاءَ قَوْمَهُ بأفْضَلَ مِمَا جِئتُكُم به، قَدْ جِئْتُكُم بخيّرِ الدُنيا والآخِرَة، وقَدْ أَمَرَنِي اللهُ تعالى أن أَدْعُوكُم إليهِ، فأيُكُم يؤازِرُنِي على هَذَا الأمر    "O Banu Abd al-Muttalib, I, indeed, don't know of any Arab youth who came to his people with a notion better than I came with.   I came to you with the goodness of this world and the Here After. Allah (swt) ordered me to call you to Him.   Who is going to support me regarding this matter? (Tabari, Tarikh at-Tabari, Vol. 2, p. 322, Ibn al-Athir, al-Kamil fi at-Tarikh, Vol. 1, p. 259) The Prophet (saw) then asked them for someone who could provide him with the protection for him and his call.  In other narrations, the Prophet (saw) said: فَأَيُّكُمْ يُبَايِعُنِي عَلَى أَنْ يَكُونَ أَخِي وَصَاحِبِي ؟   "Who of you is going to give me the pledge to be my brother and companion?" (Musnad Ahmed, Tarikh Dimashq and Tahdhib al-Kamal) These narrations (and many other similar narrations) makes more sense as the Prophet (saw) was asking for someone to protect him and his Dawah and to keep his debt and responsibilities (Tabari, Tarikh at-Tabari, Vol. 2, p. 322) in case he was injured whilst when delivering the Message. In other narrations, the Prophet (saw) stood on mount Safa and called the tribes to Allah collectively. Ibn Abbas narrated: صَعِدَ النَّبِيُّ صلى الله عليه وسلم الصَّفَا ذَاتَ يَوْمٍ فَقَالَ ‏"‏ يَا صَبَاحَاهْ ‏"‏ فَاجْتَمَعَتْ إِلَيْهِ قُرَيْشٌ قَالُوا مَا لَكَ قَالَ ‏"‏ أَرَأَيْتُمْ لَوْ أَخْبَرْتُكُمْ أَنَّ الْعَدُوَّ يُصَبِّحُكُمْ أَوْ يُمَسِّيكُمْ أَمَا كُنْتُمْ تُصَدِّقُونِي ‏"‏‏.‏ قَالُوا بَلَى‏.‏ قَالَ ‏"‏ فَإِنِّي نَذِيرٌ لَكُمْ بَيْنَ يَدَىْ عَذَابٍ شَدِيدٍ ‏"‏‏. "One day the Prophet (saw) ascended Safa mountain and said, "Oh Sabah! " All the Quraysh gathered around him and said, "What is the matter?" He said, Look, if I told you that an enemy is going to attack you in the morning or in the evening, would you not believe me?" They said, "Yes, we will believe you." He said, "I am a warner to you in face of a terrible punishment."" (Sahih al-Bukhari Hadith 4801) Conclusion The Prophet (saw) did not call non-influential individuals to Islam, rather he called tribal leaders/infuentials to Islam or the tribal members collectively. Those who became his companions (ra) heard rumours of this call and would approach the Prophet (saw) enquiring about his call. He would then tell them of revelation and conversions would follow. These companions (ra) in turn would tell others and bring them to the prophet (saw) and so on. References Tabari, Tarikh at-Tabari Ibn al-Athir, al-Kamil fi at-Tarikh Ibn 'Asakir, Tarikh Dimashq