The following passage comes from the author’s What the Victorians Made of Romanticism, which is reviewed in the Victorian Web. — George P. Landow
ecularization is a complex process and there is little consensus about what it entailed, when it happened, how long it took, and whether it is complete and irreversible. Most historians of secularization can agree, at least, on what secularization is not. It should not simply be understood negatively as the widespread loss or rejection of religious belief and neglect of religious practice. Rather, following Charles Taylor, we should think of secularization as a long, slow, multifaceted change from a society in which belief in God is the default position, to one in which, even for the most devout, belief in God is recognized as only one possibility among others.
It is not that religious belief becomes impossible in a secular age, but that even a devout believer must understand faith as a distinct construal of experience and acknowledge that other reasonable people, faced with similar circumstances, construe their experience without reference to the divine. This process is, Taylor insists, not simply a “subtraction story” (374),in which religious worldviews are sloughed off to leave a disillusioned account of experience. Rather, it requires the construction of new self-understandings in which human flourishing becomes the highest conceivable goal. . . . Secularization in nineteenth-century Britain was, first, a political process in which the state slowly relinquished its jurisdiction over the religious beliefs of its citizens. The modern secular state typically avoids endorsing any view on spiritual matters, even when its politicians are motivated by their personal religious convictions. At the start of the nineteenth century in England, this was not the case. Those who were unwilling to subscribe to the Church of England’s articles of faith faced significant obstacles to education, civic participation, and professional advancement. They could not graduate from or hold teaching positions at Oxford or Cambridge, sit in Parliament, or hold public office.
By the end of the century, these obstacles had been removed with the repeal of the Test and Corporation Acts (1828), Catholic Emancipation (1829), the decision to make English state schools nondenominational, and related measures. Without going so far as to disestablish the Church of England and remove its bishops from the House of Lords, successive governments had so limited its power over public life that full disestablishment was a step that few still thought was worth taking. In Scotland, a different but comparable process took place. Secularization in this sense describes how the state realigned its relationship toward religious belief and withdrew from doctrinal disagreements. Religious belief became privatized; it was increasingly seen as a personal affair. 
Mole, Timothy. What the Victorians Made of Romanticism: Material Artifacts, Cultural Practices, and Reception History. Princeton: Princeton University Press, 2018. [Review by George P. Landow].
Taylor, Charles. A Secular Age. Cambridge, Massachusetts: Harvard University Press, 2007.