Get the library

Using CDN

cloudflare.com

<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/flag-icon-css/3.4.3/css/flag-icon.min.css" />

Via Installation

direct

bower install flag-icon-css

via bower.json

...
"flag-icon-css": "3.4.5"
...

Usage

flag-icon

_css; rectangle flag ( […]

Loading JavaScript

simple

var oScript = document.createElement('script');
oScript.src = 'URL';
document.head.appendChild(oScript);

with callback

var oScript = document.createElement('script');
oScript.onload = function () {
    // ...code...
};
oScript.src = 'URL';
document.head.appendChild(oScript);

Loading CSS

var oLink  = document.createElement('link');
oLink.id   = cssId;
oLink.rel  = 'stylesheet';
oLink.type = 'text/css';
 […]