Mandate contract was created in Roman law, thanks to which was regulated indirect representation. The first modern civil codes have acknowledged direct representation based on a power-of-attorney but linked it to a mandate contract. The power-of-attorney as an independent institute emerged in the late 19th century under German law, with Paul Laband's theory taking the biggest credit in the separation of the power-of-attorney from the mandate contract In the case of the direct representation, the legal effects of undertaken legal acts directly occur for the represented person. Considering that when undertaking a legal act, the representative declares the will, the question arises whether the declared will should be understood as the will of the representative or the will of the represented. Answering the question, contemporary legal writers tend to see the replacement of the will of the represented by the will of the representative. Such an understanding of the nature of representation in private law has an interesting origin that dates back to the 13th century.