Edit in JSFiddle

/* Bind to multiple Backbone.js View Model's fetch completion with jQuery Deferred */

var Model1 = Backbone.Model.extend({
  // Using the response from https://gist.github.com/4531534
  url: '/gh/gist/response.json/4531534/',
});

var Model2 = Backbone.Model.extend({
  // Using the response from https://gist.github.com/4535771
  url: '/gh/gist/response.json/4535771/',
});

var View = Backbone.View.extend({
  initialize: function () {
    var _thisView = this;
    // This uses jQuery's Deferred functionality to bind render() so it runs
    // after BOTH models have been fetched
    $.when(this.options.model1.fetch(),this.options.model2.fetch())
    .done(function () {
      _thisView.render();
    });
  },
  render: function () {
    // log the number of times render() is called
    $('<li>').html('calling render()').appendTo('#log');
    // Lets just output the response into the DOM
    $('pre').html(JSON.stringify(this.options.model1.toJSON(), '', '  '));
    $('pre').append(JSON.stringify(this.options.model2.toJSON(), '', '  '));
  }
});

// Initialize the Model
var myModel = new Model1();
var myOtherModel = new Model2();

// Initialize the View, passing it the model instance
var myView = new View({
  model1: myModel,
  model2: myOtherModel
});

<a href="http://chilipepperdesign.com/2013/01/14/backbone-js-bind-callback-to-successful-model-fetch/">Bind to multiple Backbone.js View Model's fetch completion with jQuery Deferred</a>

<ul id="log"></ul>
<hr />

<pre>Loading...</pre>

a {
  font-family: arial, sans;
  margin-bottom: 2em;
  color: #000;
  display:inline-block;
  font-size: 12px;
}