The aim of the thesis is to examine a unique source so called The White Registers by Jan Jeníšek of Újezd and to Svrčovec (†1565) dating between 1539-1561. The lower nobleman Jan Jeníšek lived in the Svrčovec fortress close to the town of Klatovy. He recorded his private notes for his memory. He wrote about his economical acitivies including trade and legal matters and disputes which he led with neighbouring noblemen, burghers and subject people. Thanks to regular, frequent and detailed records the White Registers allow to introduce everyday life of a member of the lower nobility of the 16th century.