The Leibermuster pattern was developed by the Germans during the very last stages of WW2. Apparently production began in February 1945 - it was to replace all other patterns worn by the Waffen-SS and Wehrmacht.
At the very end of WW2 some troops (photographic evidence shows German troops in Czehoslovakia wearing this pattern) was issued this pattern. But it was never in widespread use during WW2.
After the war the Swiss Army introduced the pattern
The Czechoslovak Army (CSLA) introduced a quite similar pattern - but it was not identical.