diff --git a/docker-compose.yml b/docker-compose.yml
index 7f99de0..4d2c040 100644
--- a/docker-compose.yml
+++ b/docker-compose.yml
@@ -53,6 +53,8 @@ services:
       OC_PASSWORD_POLICY_MIN_UPPERCASE_CHARACTERS: "${OC_PASSWORD_POLICY_MIN_UPPERCASE_CHARACTERS:-1}"
       OC_PASSWORD_POLICY_MIN_DIGITS: "${OC_PASSWORD_POLICY_MIN_DIGITS:-1}"
       OC_PASSWORD_POLICY_MIN_SPECIAL_CHARACTERS: "${OC_PASSWORD_POLICY_MIN_SPECIAL_CHARACTERS:-1}"
+      # default language for services/WebUI; defaults to English
+      OC_DEFAULT_LANGUAGE: ${DEFAULT_LANGUAGE}
     volumes:
       - ./config/opencloud/csp.yaml:/etc/opencloud/csp.yaml
       - ./config/opencloud/banned-password-list.txt:/etc/opencloud/banned-password-list.txt