Kojęcin was formerly part of the German Empire. In the German Empire, the place was called Baumgarten.
The place is now called Kojęcin and belongs to Poland.
| Historical place name | Country | Administration | Time |
|---|---|---|---|
| Baumgarten | German Empire | Strehlen | 1939 |
| Kojęcin | Under Polish administration | Strzelin | 1945 |
| Kojęcin | Poland | Wrocław | 1992 |