diff --git a/backend/src/middleware/slugify/uniqueSlug.js b/backend/src/middleware/slugify/uniqueSlug.js
index ca37cd562..7cfb89c19 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,
+    multicharmap: { Ä: 'AE', ä: 'ae', Ö: 'OE', ö: 'oe', Ü: 'UE', ü: 'ue', ß: 'ss' },
   })
   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..d002eae03 100644
--- a/backend/src/middleware/slugify/uniqueSlug.spec.js
+++ b/backend/src/middleware/slugify/uniqueSlug.spec.js
@@ -18,4 +18,16 @@ describe('uniqueSlug', () => {
     const isUnique = jest.fn().mockResolvedValue(true)
     expect(uniqueSlug(string, isUnique)).resolves.toEqual('anonymous')
   })
+
+  it('Converts umlaut to a two letter equivalent', async () => {
+    const umlaut = 'ÄÖÜäöüß'
+    const isUnique = jest.fn().mockResolvedValue(true)
+    await expect(uniqueSlug(umlaut, isUnique)).resolves.toEqual('aeoeueaeoeuess')
+  })
+
+  it('Removes Spanish enya and diacritics', async () => {
+    const diacritics = 'áàéèíìóòúùñçÁÀÉÈÍÌÓÒÚÙÑÇ'
+    const isUnique = jest.fn().mockResolvedValue(true)
+    await expect(uniqueSlug(diacritics, isUnique)).resolves.toEqual('aaeeiioouuncaaeeiioouunc')
+  })
 })