1425 guarantee against the 'arbitrary arrests and/or seizure of property' of its members, a 1454 requirement that military forces and new taxes be approved by provincial Sejms, and statutes issued between 1496 and 1611 that prescribed the rights of commoners. Real and false nobles Nobles were born into a noble family, or adopted into a noble clan by an act of the King (this was abolished in 1633). The rarest way of achieving szlachta status was through ennoblement (naturalization) by a king or Sejm for reasons such as bravery in combat, service to the state, etc. There were claims some nobles were, in fact, usurpers who were commoners that moved to another part of the country and falsely claimed noble status. In the first half of the 16th century, hundreds of such "false nobles" were denounced by (1550–1630) in his "Liber generationis plebeanorum (Liber chamorum)", or "Book of Plebeian Genealogy (Ham's Book)". Peasants were considered descendants of Ham, the son of Noah subject to bondage under the Curse of Ham. The law forbade commoners holding landed estates and promised such estates as a reward to denouncers. Trepka was himself an impoverished nobleman who lived a town dweller's life and documented hundreds of such false claims hoping to take over one of the usurped estates. He does not seem to have succeeded in his quest despite his employment as the king's secretary. Many sejms issued decrees over the centuries in an attempt to resolve this issue, but with little success. It is unknown what percentage of the Polish nobility came from the 'lower orders' of society, but there are historians who claim nobles of such base origins formed a 'significant' element of the szlachta. Self-promotion and aggrandizement were not confined to commoners. Often, members of the lower szlachta sought further ennoblement from foreign, therefore less verifiable, sources. That is, they might acquire by legitimate means or otherwise, such as by purchase, one of a selection of foreign titles ranging from Baron, Marchese, Freiherr to Comte, all readily translatable into the Polish Hrabia. Alternatively, they would simply appropriate a title by conferring it upon themselves. An example of this is cited in the case of the last descendant of the Ciechanowiecki family, who managed to restore a genuinely old Comital title, but whose actual origins are shrouded in 18th-century mystery. Accretion of sovereignty to the szlachta The szlachta secured many rights not