There were similar sects to them from the begining, the arrians, the catars, etc.
But none of them promoted values comparable to what Christianity achieved in the Roman empire, abolishing slavery, raising the status of women, and educating people in mercy, charity and tolerance for other cultures.
In Spain for example, jews and muslims lived together and enjoyed a lot of privileges for centuries until they became a threat to Christianity's survival and were expelled from the country in 1492.
That probably saved Spain from the religion wars that asolated the rest of Europe with the Reformation that happened soon after this event.
The spanish people also fought heroically in every village against Napoleon and his French Revolutionary ideals that costed over 6,000,000 lives to implement in other countries. Not to mention the thousands of witch hunts that took place in the protestant Europe.
By their fruits you will know them...