At Christmas we celebrate the birth of Jesus Christ. His life completely altered world history. It is easy to overlook this. The trees of current events are so upfront and personal that we are unable to see the forest of Christianity’s dominance of history. In addition, the assumptions of cultural pluralism, i.e. all cultures are equally beneficial, make the obvious embarrasing. In all that follows I am going to assume the best definiton of culture that I have heard, culture is just religion externalized.
Christianity is the world’s largest religion. In 2005 the world’s population hit 6 billion. 2 billion are Christian, 1 billion are Moslem, 1 billion are Hindu/Buddhist and 2 billion are a polyglot of different beliefs.
Christianity is also the world’s most influential religion. It affects culture powerfully. To the degree that a culture embraces Christianity it has become dominant in world affairs. It is no accident that the Christian West has prevailed militarily, economically, and technologically for 2,000 years.
By contrast, the cultures dominated by Hinduism/Buddhism, Confucianism, Taosim, and especially Islam have been weak and backward. One critic recently observed that middle eastern culture, with the exception of Israel, is still culturally and technologically in the 8th century.
Christianity is dominant because it is all about Jesus Christ, whose birth we celebrated last week. Christ affects individuals and cultures positively. Here is the history since the Reformation.
At the time of the Reformation, 16th century, Spain was the world’s dominant power. It was the last time a Catholic country would hold that distinction.
By the 17th century Holland, under the influence of Calvinism, became the world’s greatest maritime power.
In the 18th and 19th century, England, transformed and fortified by 17th century Puritanism, dominated world culture. By 1914 England controlled 25% of the world’s land mass. She exported political liberty, justice, the industrial revolution, the scientific revolution, and capitalism, and thousands of missionaries to her 
dominions. The nineteenth century, dominated by Great Brittain, witnessed the greatest missionary expansion in history. See The New Shape of World Christianity: How American Experience Reflects Global Faith
by Mark Noll.
Then after WWII America, also influenced by Puritanism, picked up where England left off. We have been the world power for the last 100 years.
This is no accident. The Protestant faith heightens the value of the individual, fortifies families, provides a basis for social justice, liberates creativity, and motivates hard work, perseverance and productivity.
This is exactly what the prophet, Daniel, predicted. (Dan. 2:35) “The stone that struck the image became a great mountain that filled the earth.” Jesus anticipated this development. “The kingdom of heaven is like a grain of mustard seed that a man took and sowed in his field. It is the smallest of all seeds, but when it has grown it is larger than all the garden plants and becomes a tree, so that the birds of the air come and make nests in its branches”(Matthew 13:31–32).
Good Books on this subject are The Victory of Reason: How Christianity Led to Freedom, Capitalism, and Western Success
(above) by Rodney Stark, professor at Baylor University. Also commended is Human Accomplishment: The Pursuit of Excellence in the Arts and Sciences, 800 B.C. to 1950
by Charles Murray, one of my favorite authors. Murray is not a Christian. He is an agnostic. 
