| 15.09.1940:   | 
Z23
 is commissioned. | 
| 21-24.03.1941:   | 
Transfer of Z23
 and Z24
 to Bergen. | 
| 26-27.03.1941:   | 
Z23
 and Z24
 escort the heavy cruiser Admiral Hipper
 on its way back from the North Atlantik to Germany from Bergan to the Skagerak. | 
| 30.03-01.04.1941:   | 
The destroyers Z23
 and Z24
 and the torpedo boat Iltis
 escort the heavy cruiser Admiral Scheer
 on its way back from the North Atlantik to Germany from Norway to Germany. | 
| 20-26.05.1941:   | 
Operation Rheinübung: The destroyers Friedrich Eckoldt
, Hans Lody
, Friedirch Ihn
, Erich Steinbrinck
, Karl Galster
 and Z20
 escort the battleship Bismarck
 and the heavy cruiser Prinz Eugen
 from the Baltic Sea to Trondheim. After that, the destroyers return to Germany. | 
| 10-14.06.1941:   | 
Hans Lody
, Friedrich Eckoldt
, Karl Galster
, Z23
 and Z24
 escort the damaged cruiser Lützow
 (airborne torpedo hit) back to Germany. | 
| 16-19.06.1941:   | 
Destroyers Z23
 and Z24
 are transferred to Brest. | 
| 20-22.07.1941:   | 
The 5th destroyer flotilla of Erich Steinbrinck
, Friedrich Ihn
, Bruno Heinemann
, Z23
 and Z24
 is sent from La Pallice to Brest. On their way back, they escort the battleship Scharnhorst
 on its way to La Pallice. | 
| 24-27.07.1941:   | 
The 5th destroyer flotilla consisting of Erich Steinbrinck
, Friedrich Ihn
, Bruno Heinemann
, Z23
 and Z24
 escort the bomb damaged battleship Scharnhorst
 from La Pallice to Brest. | 
| 21-23.08.1941:   | 
Erich Steinbrinck
, Bruno Heinemann
, Z23
 and Z24
 meet the auxiliary cruiser Orion
 in the Biskay and escort it to France. | 
| 23-26.10.1941:   | 
Z23
 and Z24
 are sent back to Germany. | 
| 2911-12.12.1941:   | 
Transfer of Z23
, Z25
 and Z27
 to North-Norway. | 
| 16-18.12.1941:   | 
Operations of Z23
, Z24
, Z25
 and Z27
 against the Kola coast. After a battle against the British MTB Hazard
 and Speedy
 (hit 4 times), the destroyers return to their base. | 
| 26.12.1941:   | 
The 8.Z-Flotilla, constiting of Z23
, Z24
, Z25
 and Z27
 sails out of the Ofotfjord. | 
| 27.12.1941:   | 
Z23
, Z24
, Z25
 and Z27
 operate at the Lofoten. | 
| 03-04.01.1942:   | 
Z23
, Z24
, Z25
 and Z27
 escort the Adolf Lüderitz
 from Tromsö to Kirkenes. | 
| 13-14.01.1942:   | 
Mine operation of Z23
, Z24
 and Z25
 at Cape Kacovskij in the White Sea. | 
| 20.01.1942:   | 
The transfer of Z23
, Z24
 and Z25
 from Kirkenes to Tromsö is canceled after Z23
 and Z24
 were damaged after running aground. | 
| 27-28.01.1942:   | 
Z23
, Z24
 and Z25
 are sent from Kirkenses to Tromsö. | 
| 15-17.08.1942:   | 
Z23
, T9
 and T12
 escort the mine layer Ulm
 on its way to Narvik. | 
| 24-28.09.1942:   | 
The destroyers Richard Beizen
, Z23
, Z28
, Z29
 and Z30
 proceed to a mine laying operation at Nowaja Semlja. They are covered by the heavy cruiser Admiral Scheer
. | 
| 01-02-10.1942:   | 
The heavy cruiser Admiral Hipper
 is escorded by Z23
, Z28
, T9
 and T12
 on its way from the Altafjord to the Bogenbucht. | 
| 23-24.10.1942:   | 
Richard Beitzen
, Friedrich Eckoldt, Z23, Z28
 and Z29
 escort the battleship Tirpitz
 and the  heavy cruiser Admiral Scheer
 from Narvik to Trondheim. | 
| 06-10.11.1942:   | 
Z23
, Z28
 and Z29
 escort the heavy cruiser Admiral Scheer
 from Trondheim back to Germany. | 
| 12-18.11.1942:   | 
Z23
, Z25
 and Z29
 escort the light cruiser Nürnberg
 on its way to Trondheim. | 
| :   | 
To be continued... |