Yet pre Christian societies in Europe were arguably significantly more brutal. Establishing at least some basic principals of universal equality was a big deal (something modern atheists inherited directly from Christianity)
e.g. even amongst the civilized Greeks and and Romans foreigners who had no legal ties to their city states (some form of citizenship or diplomatic treaties with their home city) were basically treated as subhuman and could be enslaved and murdered with little to no repercussions.
Universalist religions extended that to vast geographic areas and established some basic shared principles and trust between strangers e.g. in the middle ages somebody from Scandinavia could travel to Rome on their own with relatively (of course still significant) little risk of being robbed, enslaved or murdered while being able to rely on hospitality from complete strangers/foreigners during his trip.
Of course the Romans already had something similar by the 100s AD (non citizens and slaves were of course excluded) but political systems are much more fragile than religions.
e.g. even amongst the civilized Greeks and and Romans foreigners who had no legal ties to their city states (some form of citizenship or diplomatic treaties with their home city) were basically treated as subhuman and could be enslaved and murdered with little to no repercussions.
Universalist religions extended that to vast geographic areas and established some basic shared principles and trust between strangers e.g. in the middle ages somebody from Scandinavia could travel to Rome on their own with relatively (of course still significant) little risk of being robbed, enslaved or murdered while being able to rely on hospitality from complete strangers/foreigners during his trip.
Of course the Romans already had something similar by the 100s AD (non citizens and slaves were of course excluded) but political systems are much more fragile than religions.