diff --git a/backend/src/middleware/slugify/uniqueSlug.js b/backend/src/middleware/slugify/uniqueSlug.js
index ca37cd562..abab3851a 100644
--- a/backend/src/middleware/slugify/uniqueSlug.js
+++ b/backend/src/middleware/slugify/uniqueSlug.js
@@ -2,6 +2,7 @@ import slugify from 'slug'
 export default async function uniqueSlug(string, isUnique) {
   const slug = slugify(string || 'anonymous', {
     lower: true,
+    locale: 'de',
   })
   if (await isUnique(slug)) return slug
 
diff --git a/backend/src/middleware/slugify/uniqueSlug.spec.js b/backend/src/middleware/slugify/uniqueSlug.spec.js
index ff14a56ef..684f70015 100644
--- a/backend/src/middleware/slugify/uniqueSlug.spec.js
+++ b/backend/src/middleware/slugify/uniqueSlug.spec.js
@@ -19,3 +19,17 @@ describe('uniqueSlug', () => {
     expect(uniqueSlug(string, isUnique)).resolves.toEqual('anonymous')
   })
 })
+
+describe('Slug is transliterated correctly', () => {
+  it('Converts umlaut to two letter equivalent', () => {
+    const umlaut = 'ä';
+    const isUnique = jest.fn().mockResolvedValue(true)
+    expect(uniqueSlug(string, isUnique)).resolves.toEqual('ae');
+  })
+
+  it('Removes Spanish enya ', () => {
+    const enya = 'ñ';
+    const isUnique = jest.fn().mockResolvedValue(true)
+    expect(uniqueSlug(string, isUnique)).resolves.toEqual('n');
+  })
+})