EPSG:4326 example

<!DOCTYPE html>
<html>
<head>
<title>EPSG:4326 example</title>
<script src="https://code.jquery.com/jquery-1.11.2.min.js"></script>
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.4/css/bootstrap.min.css">
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.4/js/bootstrap.min.js"></script>
<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/ol3/3.6.0/ol.css" type="text/css">
<script src="https://cdnjs.cloudflare.com/ajax/libs/ol3/3.6.0/ol.js"></script>

</head>
<body>
<div class="container-fluid">

<div class="row-fluid">
  <div class="span12">
    <div id="map" class="map"></div>
  </div>
</div>

</div>
<script>
var layers = [
  new ol.layer.Tile({
    source: new ol.source.TileWMS({
      url: 'http://demo.boundlessgeo.com/geoserver/wms',
      params: {
        'LAYERS': 'ne:NE1_HR_LC_SR_W_DR'
      }
    })
  })
];

var map = new ol.Map({
  controls: ol.control.defaults().extend([
    new ol.control.ScaleLine({
      units: 'degrees'
    })
  ]),
  layers: layers,
  target: 'map',
  view: new ol.View({
    projection: 'EPSG:4326',
    center: [0, 0],
    zoom: 2
  })
});

</script>
</body>
</html>