diff --git a/Changelog.md b/Changelog.md
index 243d18d1e..9fe538216 100644
--- a/Changelog.md
+++ b/Changelog.md
@@ -88,6 +88,7 @@ With the port to Bootstrap 3, app/views/terms/default.haml has a new structure.
 ## Refactor
 
 ## Bug fixes
+* Redirect to sign in page when a background request fails with 401 [#6496](https://github.com/diaspora/diaspora/pull/6496)
 
 ## Features
 
diff --git a/app/assets/javascripts/app/app.js b/app/assets/javascripts/app/app.js
index 4127b1225..93b0f65e3 100644
--- a/app/assets/javascripts/app/app.js
+++ b/app/assets/javascripts/app/app.js
@@ -52,6 +52,7 @@ var app = {
     this.setupGlobalViews();
     this.setupDisabledLinks();
     this.setupForms();
+    this.setupAjaxErrorRedirect();
   },
 
   hasPreload : function(prop) {
@@ -148,6 +149,22 @@ var app = {
       $(this).clearForm();
       $(this).focusout();
     });
+  },
+
+  setupAjaxErrorRedirect: function() {
+    var self = this;
+    // Binds the global ajax event. To prevent this, add
+    // preventGlobalErrorHandling: true
+    // to the settings of your ajax calls
+    $(document).ajaxError(function(evt, jqxhr, settings) {
+      if(jqxhr.status === 401 && !settings.preventGlobalErrorHandling) {
+        self._changeLocation(Routes.newUserSession());
+      }
+    });
+  },
+
+  _changeLocation: function(href) {
+    window.location.assign(href);
   }
 };
 
diff --git a/spec/javascripts/app/app_spec.js b/spec/javascripts/app/app_spec.js
index 84f4a72f3..bbdcae351 100644
--- a/spec/javascripts/app/app_spec.js
+++ b/spec/javascripts/app/app_spec.js
@@ -9,6 +9,7 @@ describe("app", function() {
       spyOn(app, "setupGlobalViews");
       spyOn(app, "setupDisabledLinks");
       spyOn(app, "setupForms");
+      spyOn(app, "setupAjaxErrorRedirect");
 
       app.initialize();
 
@@ -20,6 +21,7 @@ describe("app", function() {
       expect(app.setupGlobalViews).toHaveBeenCalled();
       expect(app.setupDisabledLinks).toHaveBeenCalled();
       expect(app.setupForms).toHaveBeenCalled();
+      expect(app.setupAjaxErrorRedirect).toHaveBeenCalled();
     });
   });
 
@@ -44,4 +46,47 @@ describe("app", function() {
       expect($.fn.placeholder.calls.mostRecent().object.selector).toBe("input, textarea");
     });
   });
+
+  describe("setupAjaxErrorRedirect", function() {
+    it("redirects to /users/sign_in on 401 ajax responses", function() {
+      spyOn(app, "_changeLocation");
+      $.ajax("/test");
+      jasmine.Ajax.requests.mostRecent().respondWith({status: 401});
+      expect(app._changeLocation).toHaveBeenCalledWith("/users/sign_in");
+    });
+
+    it("doesn't redirect on other responses", function() {
+      spyOn(app, "_changeLocation");
+
+      [200, 201, 400, 404, 500].forEach(function(code) {
+        $.ajax("/test");
+        jasmine.Ajax.requests.mostRecent().respondWith({status: code});
+        expect(app._changeLocation).not.toHaveBeenCalled();
+      });
+    });
+
+    it("doesn't redirect when error handling is suppressed", function() {
+      spyOn(app, "_changeLocation");
+      $.ajax("/test", {preventGlobalErrorHandling: true});
+      jasmine.Ajax.requests.mostRecent().respondWith({status: 401});
+      expect(app._changeLocation).not.toHaveBeenCalled();
+
+      $.ajax("/test", {preventGlobalErrorHandling: false});
+      jasmine.Ajax.requests.mostRecent().respondWith({status: 401});
+      expect(app._changeLocation).toHaveBeenCalledWith("/users/sign_in");
+    });
+
+    it("doesn't redirect when global ajax events are disabled", function() {
+      spyOn(app, "_changeLocation");
+      $.ajaxSetup({global: false});
+      $.ajax("/test");
+      jasmine.Ajax.requests.mostRecent().respondWith({status: 401});
+      expect(app._changeLocation).not.toHaveBeenCalled();
+
+      $.ajaxSetup({global: true});
+      $.ajax("/test");
+      jasmine.Ajax.requests.mostRecent().respondWith({status: 401});
+      expect(app._changeLocation).toHaveBeenCalledWith("/users/sign_in");
+    });
+  });
 });