If you mean "Christianity as an organized religion", it owes it growth and prominence to the present day mostly to the Roman Emperor Constantine, who on his accession in 324 AD made Christianity the Roman Empire's state religion.
The Old Testament is the basis of Christianity.
Christianity should be the basis of social reform.
The basis of Judaism, Christianity and Islam is the belief in the ONENESS of Almighty God (Allah - in Arabic).
there is no scientific basis for Gnosticism or orthodox (mainstream) Christianity.
Both Christianity & Islam are based on Judaism, especially Christianity.
The role that the disciples played in the development of Christianity included establishment of the church such as that began by Peter.
Christianity is the worship of Jesus Christ. Development of Christianity would have started with the disciples when they become aware and believed that Jesus was the Son of God.
The basis of Christianity is that Jesus died for our sins to save us.
Hebrewwhat early civilization most directly contributed to the development of both Christianity and Islam?
Christianity is not against Islam, though it does conflict upon the basis of faith. But from the Islamic perspective Christianity it self gives testimony for the Last prophet of Islam.
The entire basis of Christianity is a belief in God. Without this core belief, there would be no Christianity - Protestant or any other.
That is monotheism.