Edit in JSFiddle

var MyView = Backbone.View.extend({
    initialize:function(){
        this.render() //just like calling myViewInstance.render();
    },
    render:function(){
        console.log(this.el); //logs <div>
        return this;
    }
});

 //this creates a div in memory i.e. $('<div>')
var myViewInstance = new MyView({tagName:'div'});