It is unclear how you would determine this.
If you follow secular history, then Islam is a religion that has a definitive founding in history, when Mohammed first provided revelations in 610 C.E. in Arabia. Therefore, all people who preceded him would be disbelievers. If the question asks who was the first person to hear Islam and then reject it, it would be Waraqa ibn Nawfal. Even though the Ebionite believed that Mohammed was a prophet, he was not interested in changing his religion. (Ebionism was a heretical sect of Christianity.)
If you believe Islamic theology, all people were Muslims from Adam until the first polytheists like Nimrod came into existence.
To say 'disbeliever' in Arabic, you would say 'kaffir.'
First the word infidel is an incorrect translation of the word Kafer. The word Kafer simply means a disbeliever so it's not an isult it's a status. If we are from two different faith communities so I'm a disbeliever in some of the issues in your faith and you are a disbeliever in some of the issues in my faith.
atheist
The first Mu'adhin in Islam was Bilal ibn Ribah, and he was the first African convert to Islam.
There are no royalties in Islam.
Of course prophet Muhammad is the first person who believed in Islam per Quran revelation to him by God.After the prophet;The first man believed in Islam is AbouBakrThe first boy believed in Islam is Aly Ibn Abou TalebThe first woman believed in Islam is Khadija (the first prophet wife)wife
The question is fallible. One shouldn't ask how a soul ends. He/She should be focusing more about his/her soul: how he/she wants it to end. Asking how is Prophet Muhammad's parents doing is not encouraged in Islam, as it may caused misunderstanding, confusion and slanders.
which pray was the first pray in Islam and who performed it and where.
battle of Badar is the first battle that took place in islam
If one has washed oneself after becoming junub, it is mustahab [an act for which there is thawâb (blessing) and if omitted there is no sin] for one to make a ghusl for becoming a Muslim. If a disbeliever who is junub has a shower to wash the dirt, that person also gets out of the state of janâbat. For niyyat [intention] in ghusl is not fard in the Hanafî Madhhab. One is considered to have made a ghusl when one has a shower. However, if that person has not taken a shower after becoming junub, then it is fard to perform a ghusl when becoming a Muslim. (Ethics of Islam)
Islam was formed last
Islam was not discovered. It was the first religion sent to Adam.