The Unification Church (Korean: 통일교) is a new religious movement, derived from Christianity, whose members are called Unificationists or sometimes informally Moonies. Sun Myung Moon (1920–2012) began gaining followers after the Second World War. On 1 May 1954 in Seoul, South Korea, Moon formally founded the Holy Spirit Association for the Unification of World Christianity (HSA-UWC), the Unification Church's full name until 1994, when it was officially changed to the Family Federation for World Peace and Unification. It has a presence in approximately 100 countries around the world. Its leaders are Moon and his wife Hak Ja Han, whom their followers honor with the title "True Parents".

A new religious movement (NRM), also known as alternative spirituality or a new religion, is a religious or spiritual group that has modern origins and is peripheral to its society's dominant religious culture. NRMs can be novel in origin or they can be part of a wider religion, in which case they are distinct from pre-existing denominations. Some NRMs deal with the challenges that the modernizing world poses to them by embracing individualism, while other NRMs deal with them by embracing tightly knit collective means. Scholars have estimated that NRMs number in the tens of thousands worldwide. Most NRMs only have a few members, some of them have thousands of members, and a few of them have more than a million members.