Hiberna in Polish-Lithuanian Commonwealth was also known as "chleb zimowy" (winters bread) and it was an obligation to guarantee accommodation for troops during winter time. It was an obligation of Królewszczyzna (crown lands) and church estates. Initially it was paid-in-kind, in 1649-1652 it was a targeted tax to support the troops collected by Grand Crown Hetlam. Over time hiberna absorbed some other taxes (e.g. Jewish poll tax and kwarta) and extended to other population categories.
- Scepter of Judah: The Jewish Autonomy in the Eighteenth-Century Crown Poland, pp. 16-17