I was born in Buddhism family in the Buddhism country (Thailand). I had that belief all of my life, idols worshipper, no such a God, sinned etc.
One day I knew a Christian for the very first time, he told me about God. I laught and thought something like why don't he leave me alone! He tried around 1 year, I still did not believe until all the sins I committed, they hit back to my life. People who used to love me insulted me and hate me but only that Christian forgave me and helped me everything.
Today I am a Christian but I still have a lot of friends who are non-believers. One of my great friend said: I do not know your God, I know just He changed your life and you to be better very very much. Then she started to pray to God and wanted to go to church by herself.
So I think yeah.. it's important if you had been born in a different faith, you would be shaped to believe what they told you to believe. BUT when you grow up and you open your mind, you can change it to be the better one for you.
God bless you.