After the Anglo/French diplomatic mission in 1859 was destroyed by the Qing Military, a larger, more powerful diplomatic army was sent in 1860 to ram the 'Treaty of Friendship' down the throats of the Qing Court.

Despite being unable to stop this larger force militarily, the Qing Empire would attempt every conceivable tactic to delay,  misdirect, or otherwise stop the British and French from reaching Beijing and meeting the emperor. 

However as desperate as these acts were, they in the end did little but aggravate the invading Europeans, and increase bloodshed.