Final answer:
Christianity is the religion historically responsible for diminishing the old pagan ways, often incorporating and repurposing pagan practices into its own religious framework.
Step-by-step explanation:
The religion responsible for driving out the old pagan ways is Christianity. This process began earnestly during the era of the Roman Empire and continued across Europe as Christianity spread, often incorporating and repurposing pagan temples and practices in the process. Christian leaders, rather than attempting to completely eliminate pagan culture, chose to subtly transform it, allowing the transition to Christianity to be more palatable to the existing population. This pragmatic approach included rededicating pagan days of sacrifice to Christian saints and utilizing pagan celebration days for Christian holidays, such as Easter. Over time, with the support of secular rulers, Christianity became highly influential, culminating in Emperor Theodosius I declaring the Roman Empire officially Christian in 380 CE.
The spread of Christianity often involved converting pagan sites into Christian places of worship and integrating some pagan traditions into the Christian faith, ensuring that many such practices have lasted to the present day. Notable examples include the names of the days of the week, which have their roots in Norse mythology, and common superstitions like throwing salt over the shoulder to ward off evil.