diff --git a/gradle/changelog/html_language_tag.yaml b/gradle/changelog/html_language_tag.yaml
new file mode 100644
index 0000000000..f53a9bf6e2
--- /dev/null
+++ b/gradle/changelog/html_language_tag.yaml
@@ -0,0 +1,2 @@
+- type: fixed
+  description: Language tag of top level html element ([#1705](https://github.com/scm-manager/scm-manager/pull/1705))
diff --git a/scm-ui/ui-webapp/src/containers/Index.tsx b/scm-ui/ui-webapp/src/containers/Index.tsx
index 74ac89c02c..12edbc7e10 100644
--- a/scm-ui/ui-webapp/src/containers/Index.tsx
+++ b/scm-ui/ui-webapp/src/containers/Index.tsx
@@ -29,6 +29,7 @@ import ScrollToTop from "./ScrollToTop";
 import IndexErrorPage from "./IndexErrorPage";
 import { useIndex } from "@scm-manager/ui-api";
 import { Link } from "@scm-manager/ui-types";
+import i18next from "i18next";
 
 const Index: FC = () => {
   const { isLoading, error, data } = useIndex();
@@ -36,6 +37,10 @@ const Index: FC = () => {
 
   // TODO check componentDidUpdate method for anonymous user stuff
 
+  i18next.on("languageChanged", (lng) => {
+    document.documentElement.setAttribute("lang", lng);
+  });
+
   if (error) {
     return (
       <>