How did Rome's acceptance of Christianity change the world?

The adoption of Christianity by the Romans in the late Fourth Century had a dramatic impact on the world.  Early Christianity had a relatively small following and much of it was underground.  Through the infrastructure and organization of Rome, the religion gained remarkable traction and became one of the major religions of the world.  This had the effect of changing the Roman culture. Romans lost a sense of tradition and culture that they shared for centuries as their pagan beliefs became targets of the early Christian church.  Some historians attribute the adoption of Christianity as one of the causes of the fall of the Roman Empire.  The fall of the Roman Empire ushered in a period of decline called the Dark Ages.  During this time, the Roman Catholic Church enjoyed a period of great wealth and influence.  If not for the adoption of Christianity by Roman emperors, the religion may have remained obscure and underground. All of the positive and negative actions of the Roman Catholic Church in history should be attributed to the conversion of the Romans to Christianity.