A date sample in BC: <samp></samp>

<br />
<br /> 

Date '2015/04/22' in en-US format with options: <samp></samp>

body {
  font-family: bookman old style;
  font-size: 14pt;
}

samp {
  color: CRIMSON;
  font-weight: bold;
}

 var mydate = new Date(-80, 09, 07),
   options = {
     weekday: 'short',
     year: "numeric",
     month: "long",
     day: "numeric",
     era: "short"
   },
   samps = document.querySelectorAll('samp');

 samps[0].textContent = new Intl.DateTimeFormat('en-US', options).format(mydate);
 // returns "Thu, October 7, 81 BC"

 mydate = new Date('2015/04/22');
 options = {
   weekday: "short",
   year: "numeric",
   month: "long",
   day: "numeric"
 };

 samps[1].textContent = new Intl.DateTimeFormat('en-US', options).format(mydate);
 // returns "Wed, April 22, 2015"