Taken from the Hotel´s Official Website:

Being one of the oldest hotels in Warsaw - Polonia Palace Hotel - was opened on 14th July 1913. Count Konstanty Przeździecki had invested 1100 000 rubles in its premises and managed the hotel till 1939. His family had already been known for administering European Hotel in Warsaw, built by his grandfather, Aleksander. The name ‘Polonia Palace’ was not a random choice – this was a Period of Partition and such a strong patriotic accent in the heart of Vistula Land’s capital was supposed to raise the spirits of its inhabitants. The final design of the hotel emerged from the collaboration of two architects: Józef Holewiński and Juliusz Nagórski. After Neo-Renaissance Bristol Hotel, Polonia Palace became the first building in Warsaw which was entirely inspired by Parisian style, starting with a characteristic mansard roof and finishing with Louis XVI style furniture in its French restaurant, where meals were served by French waiters. Additionally the hotel offered such novelties as a telephone in each of 160 rooms and hot and cold running water, even if only six apartments were complemented with bathrooms.