The present M.A. thesis pursues the topic of hostageship for obligations in the Czech late Middle Ages, based on an analysis of epistolary correspondence, especially that between Ulrich II. of Rosenberg and his clients and opponents. Also examined are, for example, debt, purchase or mortgage agreements as a means which not only Ulrich II. tried to use for improving the bad financial situation of the house of Rosenberg. The study attempts to achieve a twofold objective: first, to clearly explain the individual terms that appear in the documents concerning the hostages, and second, based on case studies, to present an analysis of how the institute of hostageship worked in practice, with an emphasis on aristocratic honour and ties between the participants. From the methodological viewpoint, the analysis also shows that research into hostageship refines our understanding of how the Rosenberg clientele relations worked. Key words: Middle Ages, medieval, nobility, hostage, hostageship, suretyship, captivity, Kingdom of Bohemia, clients, House of Rosenberg, Ulrich of Rosenberg

La délégation en droit civil québécois est difficilement conciliable avec la conception traditionnelle de la délégation puisque le délégué peut opposer au délégataire tous les moyens que le délégant aurait pu faire valoir contre le délégataire. Cette particularité peut confondre la délégation avec la cession de dette et le cautionnement. Afin de concilier le régime de la délégation avec sa nature, la délégation peut se concevoir comme un contrat créant une obligation du délégué envers le délégataire dont l’objet est pris par référence à l’obligation du délégant envers le délégataire. Cela explique que le délégué puisse opposer au délégataire tout ce que le délégant aurait pu faire valoir contre le délégataire. Cette conception est cohérente avec le régime général de la délégation. Certaines spécificités de ce régime s’opposent à l’idée que les débiteurs sont tenus in solidum envers le délégataire, soutenant ainsi l’autonomie du régime de la délégation. La délégation se distingue de la cession de dette et du cautionnement considérant l’obligation du nouveau débiteur. À l’occasion de la cession de dette, l’obligation du nouveau débiteur est identique à celle d’un autre débiteur, tandis que l’objet de l’obligation du délégué est pris par référence à une autre obligation. À l’occasion du cautionnement, le nouveau débiteur possède une obligation dont le caractère accessoire diffère de celui de l’obligation du délégué. L’obligation de la caution a également un caractère subsidiaire qui est absent de l’obligation du délégué. La délégation est alors une notion autonome de la cession de dette et du cautionnement. / Delegation in Quebec civil law is challenging to reconcile with the traditional concept of delegation since the delegate may set up against the delegate all such defenses as the delegator could have set up against the delegatee. This peculiarity may confuse delegation with the assignment of debt and suretyship. To harmonize the delegation regime with its nature, delegation can be conceptualized as a contract creating an obligation for the delegate towards the delegatee, with the object referenced to the obligation of the delegator to the delegatee. This explains why the delegate can assert against the delegatee anything that the delegator could have claimed against the delegatee. This concept aligns with the general delegation regime. Certain specific features of this regime oppose the idea that debtors are bound in solidum towards the delegatee, thus supporting the autonomy of the delegation regime. Delegation is distinct from the assignment of debt and suretyship, considering the obligation of the new debtor. In the case of the assignment of debt, the new debtor's obligation is identical to that of another debtor, whereas the object of the delegate’s obligation is taken by reference to another obligation. In the case of suretyship, the new debtor's obligation has a different accessory nature compared to that of the delegate’s obligation. The surety's obligation also carries a subsidiary character absent from the delegate's obligation. Delegation is, therefore, an independent notion, separate from debt assignment and suretyship.

Bank demand guarantees have become an established part of international trade. Demand guarantees, standby letters of credit and commercial letters of credit are all treated as autonomous contracts whose operation will not be interfered with by courts on grounds immaterial to the guarantee or credit itself. The idea in the documentary credit transaction/demand guarantee transaction is that if the documents (where applicable) presented are in line with the terms of the credit/guarantee the bank has to pay, and if the documents do not correspond to the requirements, the bank must not pay. However, over the years a limited number of exceptions to the autonomy principle of demand guarantees and letters of credit have come to be acknowledged and accepted in practice. In certain circumstances, the autonomy of demand guarantees and letters of credit may be ignored by the bank and regard may be had to the terms and conditions of the underlying contract. The main exceptions concern fraud and illegality in the underlying contract. In this thesis a great deal of consideration has been given to fraud and illegality as possible grounds on which payment under demand guarantees and letters of credit have been attacked (and sometimes even prevented) in the English, American and South African courts. It will be shown that the prospect of success depends on the law applicable to the demand guarantee and letter of credit, and the approach a court in a specific jurisdiction takes. At present, South Africa has limited literature on demand guarantees, and the case law regarding the grounds upon which payment under a demand guarantee might be prevented is scarce and often non-existent. In South Africa one finds guidance by looking at similar South African case law dealing with commercial and standby letters of credit and applying these similar principles to demand guarantees. The courts, furthermore, find guidance by looking at how other jurisdictions, in particular the English courts, deal with these issues. Therefore, how the South African courts currently deal/should be dealing/probably will be dealing with the unfair and fraudulent calling of demand guarantees/letters of credit is discussed in this thesis. / Jurisprudence / LL.D

Bank demand guarantees have become an established part of international trade. Demand guarantees, standby letters of credit and commercial letters of credit are all treated as autonomous contracts whose operation will not be interfered with by courts on grounds immaterial to the guarantee or credit itself. The idea in the documentary credit transaction/demand guarantee transaction is that if the documents (where applicable) presented are in line with the terms of the credit/guarantee the bank has to pay, and if the documents do not correspond to the requirements, the bank must not pay. However, over the years a limited number of exceptions to the autonomy principle of demand guarantees and letters of credit have come to be acknowledged and accepted in practice. In certain circumstances, the autonomy of demand guarantees and letters of credit may be ignored by the bank and regard may be had to the terms and conditions of the underlying contract. The main exceptions concern fraud and illegality in the underlying contract. In this thesis a great deal of consideration has been given to fraud and illegality as possible grounds on which payment under demand guarantees and letters of credit have been attacked (and sometimes even prevented) in the English, American and South African courts. It will be shown that the prospect of success depends on the law applicable to the demand guarantee and letter of credit, and the approach a court in a specific jurisdiction takes. At present, South Africa has limited literature on demand guarantees, and the case law regarding the grounds upon which payment under a demand guarantee might be prevented is scarce and often non-existent. In South Africa one finds guidance by looking at similar South African case law dealing with commercial and standby letters of credit and applying these similar principles to demand guarantees. The courts, furthermore, find guidance by looking at how other jurisdictions, in particular the English courts, deal with these issues. Therefore, how the South African courts currently deal/should be dealing/probably will be dealing with the unfair and fraudulent calling of demand guarantees/letters of credit is discussed in this thesis. / Jurisprudence / LL.D