diff --git a/src/agenda_culturel/migrations/0140_alter_event_created_by_user_and_more.py b/src/agenda_culturel/migrations/0140_alter_event_created_by_user_and_more.py
new file mode 100644
index 0000000..4274cac
--- /dev/null
+++ b/src/agenda_culturel/migrations/0140_alter_event_created_by_user_and_more.py
@@ -0,0 +1,36 @@
+# Generated by Django 4.2.9 on 2025-01-31 23:37
+
+from django.conf import settings
+from django.db import migrations, models
+import django.db.models.deletion
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        migrations.swappable_dependency(settings.AUTH_USER_MODEL),
+        ('agenda_culturel', '0139_alter_message_message_type'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='event',
+            name='created_by_user',
+            field=models.ForeignKey(blank=True, default=None, null=True, on_delete=django.db.models.deletion.SET_DEFAULT, related_name='created_events', to=settings.AUTH_USER_MODEL, verbose_name='Author of the event creation'),
+        ),
+        migrations.AlterField(
+            model_name='event',
+            name='imported_by_user',
+            field=models.ForeignKey(blank=True, default=None, null=True, on_delete=django.db.models.deletion.SET_DEFAULT, related_name='imported_events', to=settings.AUTH_USER_MODEL, verbose_name='Author of the last importation'),
+        ),
+        migrations.AlterField(
+            model_name='event',
+            name='moderated_by_user',
+            field=models.ForeignKey(blank=True, default=None, null=True, on_delete=django.db.models.deletion.SET_DEFAULT, related_name='moderated_events', to=settings.AUTH_USER_MODEL, verbose_name='Author of the last moderation'),
+        ),
+        migrations.AlterField(
+            model_name='event',
+            name='modified_by_user',
+            field=models.ForeignKey(blank=True, default=None, null=True, on_delete=django.db.models.deletion.SET_DEFAULT, related_name='modified_events', to=settings.AUTH_USER_MODEL, verbose_name='Author of the last modification'),
+        ),
+    ]
diff --git a/src/agenda_culturel/models.py b/src/agenda_culturel/models.py
index cb37266..a56226c 100644
--- a/src/agenda_culturel/models.py
+++ b/src/agenda_culturel/models.py
@@ -604,6 +604,7 @@ class Event(models.Model):
         User,
         verbose_name=_("Author of the event creation"),
         null=True,
+        blank=True,
         default=None,
         on_delete=models.SET_DEFAULT,
         related_name="created_events"
@@ -612,6 +613,7 @@ class Event(models.Model):
         User,
         verbose_name=_("Author of the last importation"),
         null=True,
+        blank=True,
         default=None,
         on_delete=models.SET_DEFAULT,
         related_name="imported_events"
@@ -620,6 +622,7 @@ class Event(models.Model):
         User,
         verbose_name=_("Author of the last modification"),
         null=True,
+        blank=True,
         default=None,
         on_delete=models.SET_DEFAULT,
         related_name="modified_events"
@@ -628,6 +631,7 @@ class Event(models.Model):
         User,
         verbose_name=_("Author of the last moderation"),
         null=True,
+        blank=True,
         default=None,
         on_delete=models.SET_DEFAULT,
         related_name="moderated_events"