Some of the most influencial decisions Genghis Khan took during his life were carried out roughly during  the years 1177-1206.  It was in this period that Khan somehow managed, against all odds, to unite the previously unorganisied tribes which were dispersed throughout Mongolia.  He formed a united Mongol Confederation which was absolutely loyal to his rule.  In some cases he had to crush his more resilient enemies and massacre them but more frequent they instead chose to surrender to the invaders of his massive army.  Genghis Khan was not cruel to his subjects, he allowed individuals minor leadership roles within the clans, he shared out the wealth of his empire and was tolerant of the many different religions which existed throughout Mongolia.  He conquered tribes such as the Naimens, Merkits, Tatars, Khamag Mongols and Keraits.