A belief held by many Charismatic and Pentecostal Christians and promoted by Kingdom Now theology, Territorial Spirits are thought to be demons who rule over certain geographical areas in the world. Adherents believe that any Christian activity (such as evangelism or Church planting) requires the direct work of prayer in order to engage these spirits in spiritual warfare. Until these demons are defeated, God's work in the area cannot continue.
This belief has been promoted by the popularity of the Christian novel This Present Darkness, as well as by the ministry of C Peter Wagner.
Many Christians, including those from within the Charismatic and Pentecostal movement, argue that such a belief is a pagan concept and is unbiblical. Nevertheless, it is an increasingly popular belief.
Most of the proponents of Territorial Spirits argue that the belief is backed up implicitly in the Christian Bible, and explicitly in their experience. While no theology of demonic territoriality can be clearly identified in the Bible, proponents will point out that their experience of the phenomenon is not rejected outright either (see section on Daniel 10, below).
The use of personal experience alongside Biblical teaching as the basis for determining truth is a common one within mainstream Christianity. The belief in territorial spirits, as well as the subsequent application of this belief (Christians banding together in prayer to engage in spiritual warfare against these spirits), is not found explicitly in the Bible, but to be found in the synthesis of personal experience and Biblical teaching together - one informing the other. Christian opponents who argue that this teaching is "not Biblical" are, strictly speaking, correct. But proponents of the belief would point out that this truth has been revealed to Christians outside of, and in conjunction with, the Biblical witness. This particular argument - whether Christians should view the Bible as the sole authority (opponents to this teaching) or as one authority amongst many, albeit a very important one (proponents of this teaching) - is something that divides the church's understanding of how all truth is to be determined, and exposes conflicting epistemological standards.
Opponents to this belief will argue, however, that since the Scriptures contain enough information for the Christian "to be thoroughly equipped for every good work" (2 Timothy 3:16-17), then any information that God does not reveal in the Bible is therefore knowledge that Christians do not need in order to live an effective Christian life. While Satan and demons are mentioned in the Bible, their exact work and relationship to the spiritual world is never clearly spelt out. The belief in Territorial Spirits is not a belief that is explicitly mentioned in the Bible, so therefore many Christians who hold to this basis of authority would reject this teaching as being, at best, unhelpful and, at worst, heterodoxy.
Morevoer, opponents to this belief would argue that churches and individuals that hold to this teaching are more likely to be influenced by "false teaching" in other areas of the Christian faith, and that any qualitative research into the official teachings of these churches would confirm that a link exists between the adherence to a belief in Territorial Spirits and adherence to other teachings that are considered explicitly unbiblical.
Biblical passages used in support of Territorial Spirits
This passage concerns the visitation by a strange man to the prophet Daniel. Whether this man was an angel is disputed. This man explains to Daniel that he was delayed by the "Prince of Persia" (10:13), but was helped by "Michael, one of the chief princes" (a reference to the archangel Michael, who was recognized in Jewish literature to be a chief angel guarding over Israel). Later in that chapter, the man warns Daniel that soon the "Prince of Greece" (10:20) will join his Persian counterpart to make war upon them.
Considering the fact that Michael is generally recognized as an Angel, it is likely that the "Princes" that Michael fights against from Greece and Persia are also spiritual beings. The fact that these spirits are given names in reference to location (Greece and Persia) is a fair indication that these demonic spirits had a geographical oversight. This idea is backed up by a number of commentators (including some study Bibles).
Proponents would argue that this Biblical passage provides enough evidence to prove their point. Evil spirits exist and they are described as having power over a geographical location.
Opponents would argue that, while this passage does describe demonic spirits having power over geographical locations, it is not fully clear whether this is a description of one single recorded event, or a description of what occurs normally. The princes of Persia and Greece may well be evil Spirits recorded in the Bible in Daniel 10, but this does not logically demand that evil spirits reside in, and have control over every country, city or town in the world. Additionally, Daniel's use of apocalyptic language and vivid imagery makes it very difficult to determine the exact meaning of the chapter. Moreover, opponents would also point out that, while this passage may describe some form of demonic control over geography, it does not prescribe many of the behaviours and teachings that proponents advocate in response to this - there is no mention in Daniel 10 of God's people banding together and praying a form of "Spiritual Warfare" over the particular demons. The battles occurring in the spiritual realms, while described, have no real determining link to the actions and prayers of God's people in the physical world described in this chapter of Daniel.
Other Critical Discussions
The concept of territorial spirits and the development of specific spiritual warfare techniques has generated much discussion in the Christian missions community. Critical exchanges of views may be found in periodicals like the Evangelical Missions Quarterly  (such as in volume 31, number 2 published in 1995), and in conferences sponsored by the Evangelical Missions Society. Scholars such as Robert J. Priest, Paul Hiebert and A. Scott Moreau detect animist ideas in the arguments of supporters of the theory of territorial spirits. Robert Guelich of Fuller Theological Seminary does not find the concept of territorial spirits within the gospels, and has analyzed this problem in a critical review of Frank E. Peretti's novel This Present Darkness.
The question of territorial spirits and spiritual warfare was the topic of critical exchanges at the Lausanne Committee for World Evangelization's conference in Nairobi, Kenya in 2000. Out of this conference came a consultation document, as well as many technical papers, that was published as the book Deliver Us From Evil. The conference papers indicate some tensions in opinions as an effort was made to reach some kind of consensus view.