diff --git a/server/backend/internal/httpapi/manage/override.go b/server/backend/internal/httpapi/manage/override.go
new file mode 100644
index 0000000..466e673
--- /dev/null
+++ b/server/backend/internal/httpapi/manage/override.go
@@ -0,0 +1,134 @@
+// server/backend/internal/httpapi/manage/override.go
+package manage
+
+import (
+	"context"
+	"encoding/json"
+	"log/slog"
+	"net/http"
+	"time"
+
+	"git.az-it.net/az/morz-infoboard/server/backend/internal/mqttnotifier"
+	"git.az-it.net/az/morz-infoboard/server/backend/internal/reqcontext"
+	"git.az-it.net/az/morz-infoboard/server/backend/internal/store"
+)
+
+// globalOverrideStore ist das Interface für Handler-Tests.
+type globalOverrideStore interface {
+	Get(ctx context.Context) (*store.GlobalOverride, error)
+	Upsert(ctx context.Context, overrideType string, until time.Time) error
+	Delete(ctx context.Context) error
+}
+
+// HandleGetGlobalOverride gibt den aktuellen globalen Override zurück (204 wenn keiner aktiv).
+func HandleGetGlobalOverride(overrides globalOverrideStore) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		o, err := overrides.Get(r.Context())
+		if err != nil {
+			http.Error(w, "internal error", http.StatusInternalServerError)
+			return
+		}
+		if o == nil || time.Now().After(o.Until) {
+			w.WriteHeader(http.StatusNoContent)
+			return
+		}
+		w.Header().Set("Content-Type", "application/json")
+		json.NewEncoder(w).Encode(o) //nolint:errcheck
+	}
+}
+
+// HandleSetGlobalOverride setzt den globalen Override und schickt sofort MQTT an alle Screens.
+func HandleSetGlobalOverride(overrides globalOverrideStore, screens *store.ScreenStore, notifier *mqttnotifier.Notifier) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		var body struct {
+			Type  string    `json:"type"`
+			Until time.Time `json:"until"`
+		}
+		if err := json.NewDecoder(r.Body).Decode(&body); err != nil {
+			http.Error(w, "invalid JSON", http.StatusBadRequest)
+			return
+		}
+		if body.Type != "on" && body.Type != "off" {
+			http.Error(w, `type must be "on" or "off"`, http.StatusBadRequest)
+			return
+		}
+		if body.Until.IsZero() || !time.Now().Before(body.Until) {
+			http.Error(w, "until must be in the future", http.StatusBadRequest)
+			return
+		}
+
+		if err := overrides.Upsert(r.Context(), body.Type, body.Until); err != nil {
+			slog.Error("set global override: upsert failed", "err", err)
+			http.Error(w, "internal error", http.StatusInternalServerError)
+			return
+		}
+
+		// Sofort MQTT an alle zugänglichen Screens schicken (falls screens/notifier vorhanden)
+		if screens != nil && notifier != nil {
+			u := reqcontext.UserFromContext(r.Context())
+			var allScreens []*store.Screen
+			if u != nil {
+				switch u.Role {
+				case "admin":
+					allScreens, _ = screens.ListAll(r.Context())
+				default:
+					allScreens, _ = screens.GetAccessibleScreens(r.Context(), u.ID)
+				}
+			}
+			action := "display_" + body.Type
+			for _, sc := range allScreens {
+				if err := notifier.SendDisplayCommand(sc.Slug, action); err != nil {
+					slog.Warn("set global override: send command failed", "slug", sc.Slug, "err", err)
+				}
+			}
+		}
+
+		w.WriteHeader(http.StatusNoContent)
+	}
+}
+
+// HandleDeleteGlobalOverride entfernt den globalen Override.
+func HandleDeleteGlobalOverride(overrides globalOverrideStore) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		if err := overrides.Delete(r.Context()); err != nil {
+			slog.Error("delete global override: failed", "err", err)
+			http.Error(w, "internal error", http.StatusInternalServerError)
+			return
+		}
+		w.WriteHeader(http.StatusNoContent)
+	}
+}
+
+// HandleSetScreenOverride setzt oder löscht den per-Screen-Override (on_until: null → löschen).
+func HandleSetScreenOverride(screens *store.ScreenStore, schedules *store.ScreenScheduleStore) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		screenSlug := r.PathValue("screenSlug")
+		screen, err := screens.GetBySlug(r.Context(), screenSlug)
+		if err != nil {
+			http.Error(w, "screen not found", http.StatusNotFound)
+			return
+		}
+		if !requireScreenAccess(w, r, screen) {
+			return
+		}
+
+		var body struct {
+			OnUntil *time.Time `json:"on_until"`
+		}
+		if err := json.NewDecoder(r.Body).Decode(&body); err != nil {
+			http.Error(w, "invalid JSON", http.StatusBadRequest)
+			return
+		}
+		if body.OnUntil != nil && !time.Now().Before(*body.OnUntil) {
+			http.Error(w, "on_until must be in the future", http.StatusBadRequest)
+			return
+		}
+
+		if err := schedules.SetOverrideOnUntil(r.Context(), screen.ID, body.OnUntil); err != nil {
+			slog.Error("set screen override: db error", "screen_id", screen.ID, "err", err)
+			http.Error(w, "internal error", http.StatusInternalServerError)
+			return
+		}
+		w.WriteHeader(http.StatusNoContent)
+	}
+}
diff --git a/server/backend/internal/httpapi/manage/override_test.go b/server/backend/internal/httpapi/manage/override_test.go
new file mode 100644
index 0000000..262fcc5
--- /dev/null
+++ b/server/backend/internal/httpapi/manage/override_test.go
@@ -0,0 +1,98 @@
+// server/backend/internal/httpapi/manage/override_test.go
+package manage_test
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+	"time"
+
+	"git.az-it.net/az/morz-infoboard/server/backend/internal/httpapi/manage"
+	"git.az-it.net/az/morz-infoboard/server/backend/internal/store"
+)
+
+// --- Mocks ---
+
+type mockGlobalOverrideStore struct {
+	current      *store.GlobalOverride
+	upsertCalled bool
+	deleteCalled bool
+}
+
+func (m *mockGlobalOverrideStore) Get(_ context.Context) (*store.GlobalOverride, error) {
+	return m.current, nil
+}
+func (m *mockGlobalOverrideStore) Upsert(_ context.Context, t string, u time.Time) error {
+	m.current = &store.GlobalOverride{Type: t, Until: u}
+	m.upsertCalled = true
+	return nil
+}
+func (m *mockGlobalOverrideStore) Delete(_ context.Context) error {
+	m.current = nil
+	m.deleteCalled = true
+	return nil
+}
+
+// --- Tests ---
+
+func TestHandleGetGlobalOverride_None(t *testing.T) {
+	h := manage.HandleGetGlobalOverride(&mockGlobalOverrideStore{})
+	req := httptest.NewRequest(http.MethodGet, "/api/v1/global-override", nil)
+	w := httptest.NewRecorder()
+	h.ServeHTTP(w, req)
+	if w.Code != http.StatusNoContent {
+		t.Fatalf("want 204, got %d", w.Code)
+	}
+}
+
+func TestHandleGetGlobalOverride_Active(t *testing.T) {
+	until := time.Now().Add(time.Hour)
+	m := &mockGlobalOverrideStore{
+		current: &store.GlobalOverride{Type: "off", Until: until},
+	}
+	h := manage.HandleGetGlobalOverride(m)
+	req := httptest.NewRequest(http.MethodGet, "/api/v1/global-override", nil)
+	w := httptest.NewRecorder()
+	h.ServeHTTP(w, req)
+	if w.Code != http.StatusOK {
+		t.Fatalf("want 200, got %d", w.Code)
+	}
+	var resp store.GlobalOverride
+	if err := json.NewDecoder(w.Body).Decode(&resp); err != nil {
+		t.Fatal("decode response:", err)
+	}
+	if resp.Type != "off" {
+		t.Errorf("want type=off, got %q", resp.Type)
+	}
+}
+
+func TestHandleSetGlobalOverride_InvalidType(t *testing.T) {
+	h := manage.HandleSetGlobalOverride(&mockGlobalOverrideStore{}, nil, nil)
+	body := `{"type":"maybe","until":"` + time.Now().Add(time.Hour).Format(time.RFC3339) + `"}`
+	req := httptest.NewRequest(http.MethodPost, "/api/v1/global-override", bytes.NewBufferString(body))
+	req.Header.Set("Content-Type", "application/json")
+	w := httptest.NewRecorder()
+	h.ServeHTTP(w, req)
+	if w.Code != http.StatusBadRequest {
+		t.Fatalf("want 400, got %d", w.Code)
+	}
+}
+
+func TestHandleDeleteGlobalOverride(t *testing.T) {
+	m := &mockGlobalOverrideStore{
+		current: &store.GlobalOverride{Type: "off", Until: time.Now().Add(time.Hour)},
+	}
+	h := manage.HandleDeleteGlobalOverride(m)
+	req := httptest.NewRequest(http.MethodDelete, "/api/v1/global-override", nil)
+	w := httptest.NewRecorder()
+	h.ServeHTTP(w, req)
+	if w.Code != http.StatusNoContent {
+		t.Fatalf("want 204, got %d", w.Code)
+	}
+	if !m.deleteCalled {
+		t.Error("Delete() was not called")
+	}
+}