Answer
Neo-evangelicalism (“new evangelicalism”) was an uprising within the broader evangelical wing of Christianity that emphasized direct engagement with the culture and, in some cases, cooperation with other, more liberal Christian groups. In the early twentieth century, there was a rift in Christendom. The Fundamentalists were those who held to the fundamentals of the Christian faith (e.g., the inspiration of Scripture, the virgin birth, the deity of Christ, Christ’s substitutionary death, the second coming of Christ). The Modernists (or liberals) were ready to jettison these fundamental doctrinal positions in favor of ethics (“love your neighbor”) and religious feelings (a sense of worship and wonder). Following modern skeptical scholarship, the Modernists assumed that the Bible was simply a human book and that Jesus was a great moral teacher, and they concluded that the most important thing is that Christians love their neighbors. They were also much more willing to accept modern evolutionary theories and the possibility (or probability) that those outside of Christianity could also have a relationship with God.
As Modernists came to power in various seminaries and denominations, Fundamentalists either left voluntarily to form their own denominations and seminaries or were forced out. Fundamentalists also emphasized separation from the world and were opposed to most modern music and certain activities such as dancing, drinking, and attending movies. Since modern scholarship had led many liberals astray, there seemed to be in many cases a rejection of modern scholarship. Many Fundamentalists adopted the “fortress” mindset—that is, they would separate themselves from the world and seek to “occupy till He comes.” Fundamentalists were also fervently evangelistic.
Of course, the above is a simplistic generalization, but the rift between Fundamentalism and Modernism prevailed within Christianity for several decades. However, as time progressed, there came to be a discontent within the Fundamentalist camp. Some felt that Fundamentalists had isolated themselves too much and that Christians needed to engage the culture more directly. They also felt that, in abandoning modern scholarship, Fundamentalists had often abandoned scholarship all together. Therefore, they began to emphasize evangelical scholarship. In 1947, Carl Henry published The Uneasy Conscience of Modern Fundamentalism, which called evangelicals to distinguish themselves from the more strident and separatist forms of Fundamentalism. In the same year, Harold J. Ockenga first coined the term neo-evangelical to describe a distinct movement within Fundamentalism.
Of course, many in the Fundamentalist camp felt that these neo-evangelicals were too accommodating to the world as they abandoned some of the strict moral/cultural standards of Fundamentalism and became more open to modern scholarship.
Carl Henry was perhaps the most prominent theologian to come out of the neo-evangelical movement. Billy Graham was the most public face of the movement. The magazine Christianity Today became the voice for neo-evangelicalism.
The term neo-evangelical is still a good term for describing the historical developments in the mid-twentieth century, but it has little currency today. Most of the positions of “neo-evangelicalism” are held today by people who would simply identify themselves as “evangelical.” Of course, there are still self-described Fundamentalists who will use the term neo-evangelical to describe someone whom they think of as less than truly evangelical.
