diff --git a/CHANGELOG.rst b/CHANGELOG.rst
index 0b8bd7127d4559a8e386c96c2ae5347646c9fb7c..30ddf5cf65e31f456be0353e4a18ca2b8589ea7a 100644
--- a/CHANGELOG.rst
+++ b/CHANGELOG.rst
@@ -6,6 +6,14 @@ All notable changes to this project will be documented in this file.
 The format is based on `Keep a Changelog`_,
 and this project adheres to `Semantic Versioning`_.
 
+Unreleased
+----------
+
+Fixed
+~~~~~
+
+* ``Event.__str__`` returned a proxy type instead a string.
+
 `2.0rc2`_ - 2021-08-01
 ----------
 
diff --git a/aleksis/apps/chronos/models.py b/aleksis/apps/chronos/models.py
index 07dc3fda0bd8429f7c335093bbe0b2ae3a07b723..e4638d96b4aa1b92624bef7ea5ef62fd86dcdd1e 100644
--- a/aleksis/apps/chronos/models.py
+++ b/aleksis/apps/chronos/models.py
@@ -976,7 +976,7 @@ class Event(SchoolTermRelatedExtensibleModel, GroupPropertiesMixin, TeacherPrope
         if self.title:
             return self.title
         else:
-            return _(f"Event {self.pk}")
+            return _("Event {pk}").format(pk=self.pk)
 
     @property
     def raw_period_from_on_day(self) -> TimePeriod: