Invitation sent by Korczak to Emanuel Ringelblum and his wife for a Seder celebration on April 1, 1942 in the Orphanage. It was then housed in the interim location at 16 Sienna Street / 9 Sliska Street.

Here, at 18 Leszno street lived famous Emanuel Ringelblum.

Invitation sent by Korczak to Emanuel Ringelblum and his wife for a Seder celebration on April 1, 1942 in the Orphanage. It was then housed in the interim location at 16 Sienna Street / 9 Sliska Street. 

Emanuel Ringelblum (21.11.1900–10.03.1944) was historian, educator, social and political activist, known primarily as the creator of the underground Archive of the Warsaw Ghetto - Oneg Shabbat.

Reports by Oneg Shabbat of number of Jews that were daily sent from the Warsaw Ghetto to the death camp Treblinka. On the first day of the Gross action July 22 (22.7) 6 250 were sent to gas chambers. On the next day 7300 and on August 5h (5.8) 6 623 - among deported to death on that day was Janusz Korczak, teachers and 239 children from the orphanage Dom Sierot.

From Gazeta Zydowska, April 12, 1942.In theorczak". Description od the Seder at Korczaks Dom Sierot. Korczak ended his talk with Shalom... The author of the article, Herman Czerwinski, was a former reporter and collaborator of 'Nasz Przeglad'.