There is only one absolute good: Power.
Power is the ultimate value, the one that makes all other values possible. Those that follow their Will to Power, through discipline and sacrifice, get to enforce their values onto the rest of humanity, by force or by imitation.
People naturally seek to emulate what is strong, and associate this with "good". This is what we call Master Morality. From this the conquered.or weak build their own morality based on that of their masters, but adapted to their situation. This is what we call Slave Morality.
In an ideal state, Master morality rules and Slave morality copies and adapts. But when society is in flux sometimes this order may be reversed, leading to war and the imposicion of a new master morality, that of the victors.
This explains, for example, the evolution of a religion as complex as Christianity. When Judaism was created, the Jews were rulers of their land. Thus the Old Testament is a violent, bloody tale of conquest and subjugation, where entire cities were razed by an angry God bent ln vengeance. Master morality as its finest.
When Christianity emerged, the Jews were a conquered people, oppressed subjects of the Roman Empire, thus the New Testament speaks about forgiveness and turning the other cheek. God is a forgiving God who exists to provide confort to the righteous, sick and poor. Slave morality at its finest.
As powerful European kingdoms adopted Christianity, again the powerful elements of conquest, Jesus as the mighty Conquering Lion of Judah rather than the meek Lamb of God, were emphasized, leading to the Cruzades.