The `History.js` triggers `statechange` event for `pushState` and `replaceState` API calls. There is no way to distinguish between Back button events and API generated events. The dev branch of the library has fixed this issue. I wanted a simple fix until the fix is public. This is my attempt.

HistoryWrapper.js

if (History && History.enabled) {

  // START OF WRAPPER SECTION
  var HistoryWrapper = {
    apiEventInProgress: false,
    
    isBrowserEvent: function () {
      return !this.apiEventInProgress;
    },

    getState: function () {
      return History.getState();
    },
    
    silentExecute: function(f, data, title, url) {
      this.apiEventInProgress = true;
      var reply = f(data, title, url);
      this.apiEventInProgress = false;
      return reply;
    },
    
    pushState: function(data, title, url) {
      return this.silentExecute(History.pushState, data, title, url);
    },

    replaceState: function(data, title, url) {
      return this.silentExecute(History.replaceState, data, title, url);
    },

    onPopState: function(f) {
      var wrapper = this;
      History.Adapter.bind(window, 'statechange', function() {
        if (wrapper.isBrowserEvent()) {
          f();
        }
      });
    }
  };
  // END OF WRAPPER SECTION

  // Usage section
  
  // register onPopState callback
  HistoryWrapper.onPopState(function() {
    state = HistoryWrapper.getState();
    data = state.data;
    if ( data && (data.name == "foo-bar") ) {
      $.getScript(state.url);
    }
  });
  
  // push/replace
  HistoryWrapper.pushState({ name: "foo-bar"}, document.title, url));
  HistoryWrapper.replaceState({ name: "foo-bar"}, document.title, url + "?page=2"));
  HistoryWrapper.pushState({ name: "foo-bar"}, document.title, url + "&sort=name"));
  
}