diff --git a/apis_ontology/migrations/0045_rename_end_start_date_event_end_date_from_and_more.py b/apis_ontology/migrations/0045_rename_end_start_date_event_end_date_from_and_more.py
new file mode 100644
index 0000000..d665176
--- /dev/null
+++ b/apis_ontology/migrations/0045_rename_end_start_date_event_end_date_from_and_more.py
@@ -0,0 +1,128 @@
+# Generated by Django 5.1.4 on 2024-12-20 07:33
+
+import django_interval.fields
+from django.db import migrations
+
+migration_list = lambda model: [  # noqa: E731
+    migrations.RenameField(
+        model_name=model,
+        old_name="end_date_written",
+        new_name="end",
+    ),
+    migrations.RenameField(
+        model_name=model,
+        old_name="end_start_date",
+        new_name="end_date_from",
+    ),
+    migrations.RenameField(
+        model_name=model,
+        old_name="end_date",
+        new_name="end_date_sort",
+    ),
+    migrations.RenameField(
+        model_name=model,
+        old_name="end_end_date",
+        new_name="end_date_to",
+    ),
+    migrations.RenameField(
+        model_name=model,
+        old_name="start_date_written",
+        new_name="start",
+    ),
+    migrations.RenameField(
+        model_name=model,
+        old_name="start_start_date",
+        new_name="start_date_from",
+    ),
+    migrations.RenameField(
+        model_name=model,
+        old_name="start_date",
+        new_name="start_date_sort",
+    ),
+    migrations.RenameField(
+        model_name=model,
+        old_name="start_end_date",
+        new_name="start_date_to",
+    ),
+    migrations.AlterField(
+        model_name=model,
+        name="start",
+        field=django_interval.fields.FuzzyDateParserField(
+            blank=True, max_length=255, null=True, verbose_name="Start"
+        ),
+    ),
+    migrations.AlterField(
+        model_name=model,
+        name="end",
+        field=django_interval.fields.FuzzyDateParserField(
+            blank=True, max_length=255, null=True, verbose_name="End"
+        ),
+    ),
+]
+entities = ["event", "institution", "person", "place", "work"]
+relations = [
+    "hatreligionszugehoerigkeit",
+    "personeventlegacyrelation",
+    "personinstitutionlegacyrelation",
+    "personpersonlegacyrelation",
+    "institutioninstitutionlegacyrelation",
+    "personplacelegacyrelation",
+    "personworklegacyrelation",
+    "placeplacelegacyrelation",
+    "wargeschwistervon",
+    "warschwagerschwaegerinvon",
+    "warschwiegersohnschwiegertochtervon",
+    "warverwandtmit",
+    "hattealstrauzeugenzeugin",
+    "warpatenkindvon",
+    "dissertiertebeiunter",
+    "wurdegeborenin",
+    "starbin",
+    "erhieltausbildungin",
+    "wirkteforschtehieltsichaufin",
+    "studiertelerntean",
+    "habilitiertesichan",
+    "warassistentinan",
+    "warprivatdozentinan",
+    "warotitoprofessorinan",
+    "waraotitaoprofessorinan",
+    "warhonorarprofessorinan",
+    "warehrendoktorinan",
+    "wartaetigfuerwirkteanbei",
+    "warmitgruenderinvon",
+    "hatteleitungsfunktionan",
+    "warmitgliedvon",
+    "wargrossvatermuttervon",
+    "warrektorinan",
+    "wardekaninan",
+    "promoviertean",
+    "kaempfteinbei",
+    "warprofessorinan",
+    "graduiertean",
+    "mitbiographiertunter",
+    "warhonorardozentinan",
+    "hatteleitungsfunktionbei",
+    "nahmteilan",
+    "warelternteilvon",
+    "warschuelerinvon",
+    "warverheiratetmit",
+    "standinkontaktmit",
+    "arbeitetezusammenmit",
+    "wurdeerhobenin",
+    "wargeburtstitelvon",
+    "fandstattin",
+]
+allmodels = (
+    entities
+    + relations
+    + [f"version{entity}" for entity in entities]
+    + [f"version{relation}" for relation in relations]
+)
+
+
+class Migration(migrations.Migration):
+    dependencies = [
+        ("apis_ontology", "0044_person_alternative_names_new_and_more"),
+    ]
+
+    operations = [item for model in allmodels for item in migration_list(model)]
diff --git a/apis_ontology/models.py b/apis_ontology/models.py
index d31befb..ab3e47b 100644
--- a/apis_ontology/models.py
+++ b/apis_ontology/models.py
@@ -6,16 +6,28 @@
 from django.utils.translation import gettext_lazy as _
 
 from apis_core.apis_entities.models import AbstractEntity
-from apis_core.core.models import LegacyDateMixin
 from apis_core.utils.helpers import create_object_from_uri
 from apis_core.generic.abc import GenericModel
 from apis_core.apis_entities.abc import E53_Place
 from apis_core.history.models import VersionMixin
 from django_json_editor_field.fields import JSONEditorField
+from django_interval.fields import FuzzyDateParserField
 
 from auditlog.registry import auditlog
 
 
+class LegacyDateMixin(models.Model):
+    start = FuzzyDateParserField(
+        max_length=255, blank=True, null=True, verbose_name=_("Start")
+    )
+    end = FuzzyDateParserField(
+        max_length=255, blank=True, null=True, verbose_name=_("End")
+    )
+
+    class Meta:
+        abstract = True
+
+
 class OEBLBaseEntity:
     pass
 
diff --git a/apis_ontology/settings.py b/apis_ontology/settings.py
index 59607e4..5558610 100644
--- a/apis_ontology/settings.py
+++ b/apis_ontology/settings.py
@@ -14,6 +14,7 @@
 INSTALLED_APPS += ["auditlog", "apis_acdhch_django_auditlog"]
 INSTALLED_APPS.remove("apis_core.apis_relations")
 INSTALLED_APPS += ["django_json_editor_field"]
+INSTALLED_APPS += ["django_interval"]
 
 ROOT_URLCONF = "apis_ontology.urls"
 
diff --git a/apis_ontology/urls.py b/apis_ontology/urls.py
index cc766c5..7fd6d1d 100644
--- a/apis_ontology/urls.py
+++ b/apis_ontology/urls.py
@@ -11,3 +11,4 @@
 urlpatterns += [
     path("", include("apis_acdhch_django_auditlog.urls")),
 ]
+urlpatterns += [path("", include("django_interval.urls"))]
diff --git a/pyproject.toml b/pyproject.toml
index a6731fa..1d28174 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -16,6 +16,7 @@ apis-acdhch-default-settings = "1.8.0"
 django-auditlog = "^3.0.0"
 apis-acdhch-django-auditlog = "^0.2.0"
 django-json-editor-field = "^0.4.0"
+django-interval = "^0.2.3"
 
 [tool.poetry.group.dev.dependencies]
 ruff = "^0.8.0"