In a decisive <a href="https://en.wikipedia.org/wiki/Yongle_Emperor's_campaigns_against_the_Mongols" id="mwVg" rel="mw:WikiLink" title="Yongle Emperor's campaigns against the Mongols">battle at Onon River</a>, the Mongol forces of <a class="mw-redirect" href="https://en.wikipedia.org/wiki/Oljei_Temur" id="mwVw" rel="mw:WikiLink" title="Oljei Temur">Oljei Temur</a> were decimated by the Chinese armies of the <a href="https://en.wikipedia.org/wiki/Yongle_Emperor" id="mwWA" rel="mw:WikiLink" title="Yongle Emperor">Yongle Emperor</a>.