Invading <a class="mw-redirect" href="https://en.wikipedia.org/wiki/Rattanakosin_Kingdom" id="mwWw" rel="mw:WikiLink" title="Rattanakosin Kingdom">Siamese</a> forces attempt to exploit the political chaos in <a href="https://en.wikipedia.org/wiki/Vietnam" id="mwXA" rel="mw:WikiLink" title="Vietnam">Vietnam</a>, but are ambushed and annihilated at the <a href="https://en.wikipedia.org/wiki/Mekong" id="mwXQ" rel="mw:WikiLink" title="Mekong">Mekong</a> river by the <a class="mw-redirect" href="https://en.wikipedia.org/wiki/Tây_Sơn" id="mwXg" rel="mw:WikiLink" title="Tây Sơn">Tây Sơn</a> in the <a href="https://en.wikipedia.org/wiki/Battle_of_Rạch_Gầm-Xoài_Mút" id="mwXw" rel="mw:WikiLink" title="Battle of Rạch Gầm-Xoài Mút">Battle of Rạch Gầm-Xoài Mút</a>.