Scroll horizontally starting from right to left with CSS overflow:scroll

You can of course use direction:rtl

document.querySelector('input').addEventListener('input', function(){
  document.querySelector('.box').scrollLeft = this.value;
})

.box{
  width: 320px;
  height: 100px;
  border:1px solid red;
  overflow: scroll;
  direction: rtl;  /* <-- the trick */
}

.box::before{ content:''; display:block; width:400%; height:1px; }

<div class='box'></div>
<br>
<input placeholder='scrollLeft value'>

FiddleDemo

This may be useful using direction http://css-tricks.com/almanac/properties/d/direction/

I don't Know about any solution with just CSS but you can use Jquery to change the initial position of the scrollbar like this:

$(document).ready(function(){
    $('#box').scrollLeft($(this).height())
})

Check this Demo Fiddle

With javascript you can just set scrollLeft property when page gets loaded (using el.scrollLeft = el.scrollWidth - el.clientWidth;).