Sonntag was formerly part of the German Empire. In the German Empire, the place was called Sonntag.
The place is now called Zyndaki and belongs to Poland.
| Historical place name | Country | Administration | Time |
|---|---|---|---|
| Sonntag | German Empire | Sensburg | 1939 |
| Zyndaki | Under Polish administration | Mrągowo | 1945 |
| Zyndaki | Poland | Olsztyn | 1992 |