Construction of the Bazar building, prompted by Karol Marcinkowski, took place between 1838-42. It was designed by Ernest Steudener and the engineering work was supervised by Antoni Krzyżanowski. Originally, this late Classicist edifice stood facing the present Paderewski Street. In 1899, in place of a demolished townhouse of the Łęckis, a west wing was built with a facade looking out on Marcinkowski Avenue. An extension designed by Roger Sławski was destroyed in 1945, but it was rebuilt by 1949.
In keeping with the original intention of its creators, Bazar became a hub of the Polish economic and social life during the Prussian occupation. The hotel was used by visiting Great Poland landowners. On the ground floor there were shops of Polish merchants, including a hardware store of Hipolit Cegielski. The parlours were used for patriotic ceremonies, lectures, concerts and balls. The building was also the stage of many important historical events. During the Spring of Nations (1948) it was the residence of the National Committee. When the building came under fire with Ignacy Paderewski as its guest, the incident sparked the Great Poland Insurrection (1918-19). Many personages from the world of politics, science and culture stayed here. In the 30's Jan Kiepura sang from a balcony that existed back then for a crowd gathered outside.
On the outside wall on the corner of Marcinkowski Avenue and Paderewski Street there is a commemorative plaque from 1928. It was designed by Stanisław Jagmin and was put up to honour the memory of composer and Prime Minister- I. J. Paderewski. The plaque was destroyed and recreated in 1978.