title: Cannot call 'start' of undefined when starting backbone.js history.
body: <p>I get <code>Cannot call 'start' of undefined</code> when calling...</p>
  
  <pre><code>    Backbone.history.start()
  </code></pre>
  
  <p>When running some checks Backbone returns the object but Backbone.history returns undefined. </p>
  
  <p>What could be the cause of this?</p>
  
  <p>Thanks</p>