diff --git a/firefly/Dockerfile b/firefly/Dockerfile
index 7a0d78f..29fbc3f 100644
--- a/firefly/Dockerfile
+++ b/firefly/Dockerfile
@@ -1,9 +1,13 @@
 FROM jc5x/firefly-iii:latest
 
-# Install cron & crontab
+ARG LOCALE
+
+# Install cron; setup locales
 RUN apt update && \
 apt install --no-install-recommends -y cron && \
-echo "0 */4 * * * /usr/bin/php /var/www/html/artisan firefly-iii:cron" | crontab
+echo "0 */4 * * * /usr/bin/php /var/www/html/artisan firefly-iii:cron" | crontab && \
+echo "$LOCALE.UTF-8 UTF-8" >> /etc/locale.gen && \
+locale-gen
 
 # Run cron on startup
 ENTRYPOINT cron && /usr/local/bin/entrypoint.sh
diff --git a/firefly/docker-compose.yml b/firefly/docker-compose.yml
index 60e5612..719e814 100644
--- a/firefly/docker-compose.yml
+++ b/firefly/docker-compose.yml
@@ -5,6 +5,8 @@ services:
         build:
             context: '.'
             dockerfile: './Dockerfile'
+            args:
+                - 'LOCALE=$DEFAULT_LOCALE'
         image: 'firefly-iii-cron:latest'
         restart: 'always'