Human
Bellum omnium contra omnes
Morality is abstract but it is inherent in humanity irrespective of religion or non religion.
What religion does is it grounds morality, atheism can often do the opposite, just look at the first few decades of the atheist soviet union and its complete disregard for human life and rights for human beings.
Possibly in their eyes it was justifiable due to them redefining morality in the eyes of atheism.
Nietzche one of the most greatest atheists, concludes in his magnum opus that for the new atheist man to fill in these holes left behind once religion or God is removed, man himself must become God.
In other words, we define mortality based on our limited concepts of it, this will end in failure.
Religion and morality are aspects of life that are part of the same family but it differs depending on the context these two terms are used.
Religion and atheism are two concepts that have certain beliefs that hold a certain fundamental to it. These terms, or concepts I may say, are not the fault of any certain event or incident that takes place in human history but it is the people that use it that are at fault(or not at fault if they use it correctly).
If I do remember, atheism or anti-religious thought has played a significant role in our human history. There were a significant concern of bloodshed and savagery caused by Christians in Europe which they used their religion to back their actions up. Luckily, the Enlightenment occurred which went against such ideologies and these 'religious' savages' influence dimmed whilst tolerance, scholasticism and deism had increased. Therefore, without people like Immanuel Kant, there wouldn't be a tolerance of people doing particular things for the name of religion.
Nietzche also said 'Morality is the herd-instinct of the individual' which means individuals do particular things for their societies and to meet their society's expectations rather than doing good or bad because that particular individual wants to do good.
It depends. Religious upbringing is not the only thing that helps contribute if one is moral or not but many other factors. Surely, the words 'good' and 'bad' are simply easy to understand and implement in your life. If you truly understand the meaning of those words then your morality shall not be lost.