The author’s research into the clerical careers of particular representatives of the Rudzki family, and into their incomes and possessions leads to the following conclusions. The Rudzkis did not belong to the oldest native gentry of the Cieszyn Duchy, who date back to the second half of the 14th c. (like, for example, the Czelowie of Czechowice), or, in some cases, even to the turn of the 14th c. which was the period where this social class was coming into being in the newly created Cieszyn Duchy. The first representatives of the Rudzki family appeared in the social surroundings of the Dukes of Cieszyn already in the last quarter of the 15th c. but we can talk about their real presence in the said area only beginning with the 1520s, that is since there appeared, at the court of the Cieszyn branch of the Piast dynasty, Erasmus Rudzki. Having received, from the Duke Casimir II, the „Parchowo” manor, in the village Bobrek adjacent to the town of Cieszyn, the Rudzkis were granted the privilege to settle down, and from that time on they could see themselves as members of the Cieszyn gentry, and could enjoy all privileges proceeding from this fact. Bearing in mind that, in the 14th c. and early 15th c. the Cieszyn gentry were hardly numerous, and the majority of the noble families consisted of people who arrived from outside the Duchy, we may classify the Rudzkis as typical representatives of that class, whose members were looking for somewhere to live in various regions of the Upper Silesia. Erasmus’s earning the trust of Duke Casimir made it possible for him to gain the position of the president of the council of the Duchy of Cieszyn. Most probably, the duke entrusted him with the education of his grandson - Wenceslas III Adam. Thanks to that, Erasmus introduced into the ducal court his sons: Wenceslas and Nicholas, which we can surmise considering the exceptional positions that, in the not too distant future, both Rudzkis held at the ducal court. Wenceslas Ill Adam’s trust that Erasmus’s sons and grandsons’ won paved the way to such careers that no other noble family in the Duchy of Cieszyn have ever, either earlier or later, made. Erasmus’s two sons took proper care of the promotion of their brothers: Melchior and Caspar. The former became the overseer of the duke’s landed property in the Demesne of Cieszyn, while the latter was a manager of the Demesne of Skoczów. All the above-mentioned persons held their posts until they died, which shows that they did not betray the trust that they had won. The Rudzkis’ further career was stopped for a while because there was no experienced, adult, male representative of the family after the death of the two most important officials - the chancellor Wenceslas and the president Nicholas. Wenceslas, however, following his father’s, Erasmus’s, example, managed to place his sons, Caspar and Erasmus, in the milieu of the under-age Duke Adam Wenceslas, the son of Wenceslas III Adam, which enabled them later to hold, at the ducal court, the positions analogous to the ones held earlier by their father and paternal uncle. The former became the overseer of the Demesne of Cieszyn, and later the chancellor (until 1608), and president of the Cieszyn regional council, and, for some time, also a district judge. Erasmus took over from his brother the post of the chancellor, and, for a short period at the end of his life, also held that of the council president. The death of both dignitaries coincides with the political changes in the Duchy of Cieszyn, which were connected, first of all, with the extinction of the Piast dynasty, and also with the military actions during the Thirty Years War. At the same time, the male line of the Rudzki family in the Duchy of Cieszyn died out. The family’s importance, both in the political and material sense, declined.