diff --git a/src/calibre/db/backend.py b/src/calibre/db/backend.py
index 9ba5a3e348..5bba130b48 100644
--- a/src/calibre/db/backend.py
+++ b/src/calibre/db/backend.py
@@ -991,6 +991,9 @@ class DB:
         if note_id is not None:
             yield from self.notes.resources_used_by(conn, note_id)
 
+    def unretire_note(self, field, item_id, item_val):
+        return self.notes.unretire(self.conn, field, item_id, item_val)
+
     def initialize_fts(self, dbref):
         self.fts = None
         if not self.prefs['fts_enabled']:
diff --git a/src/calibre/db/notes/connect.py b/src/calibre/db/notes/connect.py
index dc8958afd9..fddb2a7c6b 100644
--- a/src/calibre/db/notes/connect.py
+++ b/src/calibre/db/notes/connect.py
@@ -13,6 +13,7 @@ from typing import Optional, Union
 from calibre.constants import iswindows
 from calibre.utils.copy_files import WINDOWS_SLEEP_FOR_RETRY_TIME
 from calibre.utils.filenames import copyfile_using_links, make_long_path_useable
+from calibre.utils.icu import lower as icu_lower
 
 from ..constants import NOTES_DIR_NAME
 from .schema_upgrade import SchemaUpgrade
@@ -130,7 +131,7 @@ class Notes:
     def retire_entry(self, field_name, item_id, item_value, resources, note_id):
         path = make_long_path_useable(os.path.join(self.backup_dir, field_name, str(item_id)))
         if os.path.exists(path):
-            key = (item_value or '').lower()
+            key = icu_lower(item_value or '')
             destdir = os.path.join(self.retired_dir, hash_key(f'{field_name} {key}'))
             os.makedirs(make_long_path_useable(destdir), exist_ok=True)
             dest = os.path.join(destdir, DOC_NAME)
@@ -145,7 +146,7 @@ class Notes:
             self.trim_retired_dir()
 
     def unretire(self, conn, field_name, item_id, item_value) -> int:
-        key = (item_value or '').lower()
+        key = icu_lower(item_value or '')
         srcdir = make_long_path_useable(os.path.join(self.retired_dir, hash_key(f'{field_name} {key}')))
         note_id = -1
         if not os.path.exists(srcdir) or self.note_id_for(conn, field_name, item_id) is not None:
diff --git a/src/calibre/db/tests/notes.py b/src/calibre/db/tests/notes.py
index 0b9e3c60fa..68be4dde47 100644
--- a/src/calibre/db/tests/notes.py
+++ b/src/calibre/db/tests/notes.py
@@ -79,8 +79,14 @@ def test_cache_api(self):
     # test removing author from db retires notes
     cache.set_field('authors', {bid:('New Author',) for bid in cache.all_book_ids()})
     self.ae(len(cache.all_field_ids('authors')), 1)
-    before = os.listdir(notes.retired_dir)
-    self.ae(len(before), 1)
+    self.ae(len(os.listdir(notes.retired_dir)), 1)
+    # test re-using of retired note
+    cache.set_field('authors', {1:'Author One'})
+    author_id = cache.get_item_id('authors', 'Author One')
+    self.ae(cache.notes_resources_used_by('authors', author_id), frozenset({h1, h2}))
+    self.ae(cache.get_notes_resource(h1)['data'], b'resource1')
+    self.ae(cache.get_notes_resource(h2)['data'], b'resource2')
+    self.assertFalse(os.listdir(notes.retired_dir))
 
 
 class NotesTest(BaseTest):
diff --git a/src/calibre/db/write.py b/src/calibre/db/write.py
index 27bf6879fc..d0442caf53 100644
--- a/src/calibre/db/write.py
+++ b/src/calibre/db/write.py
@@ -297,6 +297,8 @@ def get_db_id(val, db, m, table, kmap, rid_map, allow_case_change,
             table.asort_map[item_id] = aus
         if hasattr(table, 'link_map'):
             table.link_map[item_id] = ''
+        if table.supports_notes and isinstance(val, str):
+            db.unretire_note(table.name, item_id, val)
     elif allow_case_change and val != table.id_map[item_id]:
         case_changes[item_id] = val
     val_map[val] = item_id
@@ -380,7 +382,8 @@ def many_one(book_id_val_map, db, field, allow_case_change, *args):
     # Remove no longer used items
     remove = {item_id:item_val for item_id, item_val in table.id_map.items() if not table.col_book_map.get(item_id, False)}
     if remove:
-        db.clear_notes_for_category_items(table.name, remove)
+        if table.supports_notes:
+            db.clear_notes_for_category_items(table.name, remove)
         db.executemany('DELETE FROM %s WHERE id=?'%m['table'],
             ((item_id,) for item_id in remove))
         for item_id in remove:
@@ -484,7 +487,8 @@ def many_many(book_id_val_map, db, field, allow_case_change, *args):
     # Remove no longer used items
     remove = {item_id:item_val for item_id, item_val in table.id_map.items() if not table.col_book_map.get(item_id, False)}
     if remove:
-        db.clear_notes_for_category_items(table.name, remove)
+        if table.supports_notes:
+            db.clear_notes_for_category_items(table.name, remove)
         db.executemany('DELETE FROM %s WHERE id=?'%m['table'],
             ((item_id,) for item_id in remove))
         for item_id in remove: