Based on a provision made during the Council of Trent (1545 – 1563), the Catholic church started to maintain not only registers of births, marriages, deaths, and confirmations but also so-called Parish Census Books; in Latin libri status animarum (books of the state of souls). It was intended that parish priests would record at regular intervals a list of all persons within their parish district. This provision was adopted in Bohemia in 1605 and in Moravia in 1591. In the Rituale Romanum published in 1614 by Pope Paul V, a uniform form of entry was prescribed. At first the lists only contained brief data including the names of parishioners, their churchmanship, and sacraments received.  Later, other data was collected such as age, house number, occupation, or social status. The parish census books were not kept as diligently as the parish registers and the structure of the records vary in different parishes.

Parish census books were frequently used in the Czech lands during the counter-reformation in the 17th century. They were originally used to control the population’s religious affiliation and were conducted at long intervals. The records served secular as well as ecclesiastical purposes. With the introduction of state-organized population enumerations during the second half of 18th century, the libri status animarum had lost practically all importance and were mostly discontinued.

Although large numbers of parish census books were destroyed, some can still be found as part of the parish office archive files. They are usually in the form of a book, sorted by individual villages within the parish district. Parish census books list all inhabitants by household, which includes family members, but also subtenants, farm hands, and servant girls. This view of whole households can be of great interest, especially if other enumerations of inhabitants and older censuses have not been preserved.