The kwarta () or quarter tax was a tax in Polish–Lithuanian Commonwealth on all incomes from crown estates in (crown lands). Scepter of Judah: The Jewish Autonomy in the Eighteenth-Century Crown Poland, p 17 It was established in 1563.Norman Davies, God's Playground, p. 97
Initially the rate was 1/4, hence the name, later 1/5. Its purpose was to maintain the Kwarta army. Later it was absorbed into the hiberna military-purpose tax.
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