In 1534, King Henry parted with the Pope and the Catholic religion and by the Act of Supremacy made himself the supreme head of the church in his lands.

All clergymen, parish priests, heads of monasteries, colleges, hospitals and other institutions under church auspices were commanded to give sworn testimony before their local commissioners as to their income, the lands their establishments owned and the revenues they received from all other sources.

The commissioners were unpaid and untrained, mostly local gentry, mayors, magistrates, bishops and sheriffs, but they approached the vast task with speed and, by the summer of 1535, the government had in its hands a detailed accounting of the property and wealth of the church.

Where the figures can be checked, for example against the financial records of the king's officials in charge of dissolving monasteries in the later 1530s, they are shown to be broadly accurate though on the low side, in some cases by as much as 15%.

In a few instances the discrepancy is of so large a scale as to suggest deliberate fraud in the returns in the Valor Ecclesiasticus; as was the case for example of Norton Priory in Cheshire, where the submitted figure was so low as to render the abbey liable for suppression under the first (1536) statute for the dissolution of lesser religious houses.