The Reformation in Europe opened the floodgates for new denominations to emerge. Through the previous centuries of Roman Catholic domination, various people had disagreed with the establishment and each other. But Roman Catholic authorities had suppressed their voices. The Reformation changed much of that. More people felt free to voice their views. Strong leaders gathered followers and eventually formed them into denominations—separate bodies with separate names. Any Bible reader can know that conflicting parties and divisions contradict the unity for which Christ prayed.
I do not ask for these [apostles] only, but also for those who will believe in Me through their word, that they may all be one, just as you, Father, are in Me, and I in you, that they also may be in us, so that the world may believe that you have sent Me. (John 17:20-21)
Nevertheless, the Reformation, instead of bringing believers together around Christ, had the opposite effect. It began in a divided way and laid the groundwork for many more divisions. Today, worldwide, sociologists estimate that separate religious bodies claiming to be Christian exceed 40,000. In the face of such variety and confusion, this survey can only touch on a few developments. If your denomination is mentioned, there is no intention to single it out in a critical way. It simply helps to illustrate how larger trends have taken shape.