Letter of Prophet Muhammad to Negus (Najashi) Calling him to Islam

Late in the six year A.H., on his return from Hudaibiyah, the Prophet Muhammad , decided to send messages to the kings beyond Arabia calling them to Islam. In order to authenticate the credentials of his envoys, a silver seal was made in which were graven the words: “Muhammad the Messenger of Allâh” [Sahih Al-Bukhari 2/872,873]
The following letter was sent to Negus (Najashi)

“In the Name of Allah, the Most Beneficent, the Most Merciful.
From Muhammad the Messenger of Allah to Negus, king of Abyssinia (Ethiopia).
Peace be upon him who follows true guidance. Salutations:
I entertain Allah’s praise, there is no god but He, the Sovereign, the Holy, the Source of peace, the Giver of peace, the Guardian of faith, the Preserver of safety. I bear witness that Jesus, the son of Mary, is the spirit of Allah and His Word which He cast into Mary, the virgin, the good, the pure, so that she conceived Jesus. Allah created him from His spirit and His breathing as He created Adam by His Hand. I call you to Allah Alone with no associate and to His obedience and to follow me and to believe in that which came to me, for I am the Messenger of Allah. I invite you and your men to Allah, the Glorious, the All-Mighty. I hereby bear witness that I have communicated my message and advice. I invite you to listen and accept my advice.
Peace be upon him who follows true guidance.”

When ‘Amr bin Omaiyah Ad-Damari communicated the prophet’s letter to Negus (Najashi), the latter took the parchment and placed it on his eye, descended to the floor, confessed his faith in Islam and wrote the following reply to the Prophet :

“In the Name of Allah, the Most Beneficent, the Most Merciful.
From Negus Ashama to Muhammad, the Messenger of Allah.
Peace be upon you, O Messenger of Allah! and mercy and blessing from Allah beside Whom there is no god. I have received your letter in which you have mentioned about Jesus and by the Lord of heaven and earth, Jesus is not more than what you say. We fully acknowledge that with which you have been sent to us and we have entertained your cousin and his companions. I bear witness that you are the Messenger of Allah, true and confirming (those who have gone before you), I pledge to you through your cousin and surrender myself through him to the Lord of the worlds.”

Source: [Za'd Al-Ma'ad 3/60, 61] by Ibn Al-Qayyim
According to Sahih Muslim, the Prophet [s.a.w.s.] had asked Najashi to send Ja‘far and his companions, the emigrants to Abyssinia (Ethiopia), back home. They came back to see the Prophet [s.a.w.s.] in Khaibar. Najashi later died in Rajab 9 A.H. shortly after the battle of Tabuk. The Prophet announced his death and observed prayer in absentia for him. Another king succeeded Negus to the throne and another letter was sent to him by the Prophet (s.a.w.s.) but whether or not he embraced Islam is still a question not answered yet. [Sahih Muslim 2/99]