In the collection of the State Archaeological Museum in Warsaw there is documentation which contains information about the process of origin and the first years of activity of the Society for the Protection of Monuments of the Past. It also informs about the role of one of its founder members - Erazm Majewski. He began the cooperation in November 1905. He consulted the outline of the “Act,” which defined aims and tasks of the organisation which was coming into existence. He also invented its name - Towarzystwo Opieki nad Zabytkami Przeszłości (TOnZP) - “The Society for the Protection of Monuments of the Past”. Due to the organisatorial talent, entrepreneurship, scientific authority and considerable financial resources of E. Majewski, he was registered on the list of founder members in September 1906. In March 1907 he was elected for one of the vice-presidents of the Board of the Society. Meetings soon began to take place once a month and E. Majewski often presided over them. He actively joined the process of formation of structures of the Society and the accomplishment of its tasks. He inventoried a precious book collection from Łohojsk, which was granted to the Society by the Tyszkiewicz family and which contained more than 2000 volumes. He visited archaeological sites which were being discovered in the neighbourhood of Warsaw. He also enforced a project of foundation of an autonomous Museum at the TonZP. The share of E. Majewski in subsidising the activity of the Society and financially supporting its numerous initiatives was considerable. Already in November 1906 he hosted the Society by assigning one of the rooms in his house in ul. Złota 61 for the Society’s seat. He declared 15 000 roubles for the purchase or construction of the own seat of the TonZP. He granted 25 roubles for photographic plates for the Inventory Lab which was brought into existence. It prepared and stored photographic documentation. E. Majewski personally participated in negotiations with Wiktor Gomulicki concerning the acquisition of his unique collection of Varsaviana for the Society and granted 100 roubles for this purpose. After the death of the President of the TonZP Adam Count Krasiński, E. Majewski was elected for the President of the Society in 1910. However, he did not accept this function. His decision was mostly influenced by his steadily deteriorating state of health and the fact that he devoted too much time, forces and energy to his scientific and social activity, to managing his own Archaeological Museum and to his professional work, by which he made his living. His resignation from intensive work in the TonZP did not mean, however, a complete breach of contacts. Both the fate of the Society and events related to its activities were of vivid interest to E. Majewski. When in March 1911 a decision was made to purchase the house of the Baryczkas in Rynek Starego Miasta 32 in Warsaw, he granted the previously declared enormous sum of 15 000 roubles for this purpose. As the main donor he was invited for the solemn opening of the new premises on 5 June 1912. The opening was inaugurated by a sumptuous exhibition of “Polish miniatures, fabrics and embroideries.” In the following years he eagerly participated in opening ceremonies of subsequent exhibitions. The vestibule of the Baryczkas house became in 1914-1916 the place of deposit of the largest relic in the collection of the Museum of Erazm Majewski, i.e., a 9 m longdugout canoe. E. Majewski died on 14 November 1922. At a special meeting of the TonZP it was decided to fund a commemorative plaque in his honour and in recognition of his merits.