Ljudvigsort was formerly part of the German Empire. In the German Empire, the place was called Ludwigsort.
The place is now called Laduškin and belongs to Russian Federation.
| Historical place name | Country | Administration | Time |
|---|---|---|---|
| Ludwigsort | German Empire | Heiligenbeil | 1939 |
| Ljudvigsort | Under Soviet administration | Kaliningrad | 1945 |
| Laduškin | Russian Federation | Bagrationovsk | 1992 |