By 1840 the Tchetchnia tribes of the wooded lowlands under the mountains had broken out into outrageous rebellion, for Shamil had established himself in the forests, and was harassing the whole Russian border. 'We have never,' wrote General Golovine, 'had in the Caucasus an enemy so savage and dangerous as Shamil'; and it was again decided to send an overwhelming army against him. The two first expeditions virtually failed. Between 1839 and 1842 the Russians had lost in killed or wounded 436 officers and 7930 men, and 'had accomplished little or nothing.' In 1844 the Emperor Nicholas had despatched large reinforcements to the Caucasus, with stringent orders to make an end of Shamil's 'terrible despotism' and to subdue the whole country. On his side Shamil mustered all his forces for an energetic defence. His mounted bands traversed the borderlands with amazing rapidity, rushing in suddenly upon the Russian outposts, waylaying detachments, and bewildering the commanders by the speed and secrecy of their movements. Count Vorontzoff marched against him with an army of about 18,000, horse, foot, and artillery. Shamil retreated gradually before him, drawing on the Russians, and abandoning his forward positions after a show of defending them. He had laid waste the country on the line of the Russian advance; so, as supplies were running very short, Vorontzoff pushed on hastily toward Shamil's headquarters at Dargo. This place, surrounded by forests, 'lay along the crest of a steep wooded spur of the Betchel ridge, nowhere very broad, narrowed here and there to a few feet, and consisting of a series of long descents with shorter intervening rises. Abattis of giant trunks with branches cunningly interlaced barred the way at short intervals, and the densely-wooded ravines on either side swarmed with hidden foes.'