After a time of self-chosen seclusion, Zhabdrung proclaimed his intention to become the spiritual and temporal ruler of Bhutan. While the Drukpa Kagyu, Sakya, and Nyingma schools as well as many chieftains accepted his political domination, several other lamas did not and continued to resist him. As he consolidated his control over the western valleys, Zhabdrung began to construct a strategically placed dzong as his seat of power in 1629. It was during the construction that five lamaist factions attacked his party and his supporters. The following First Battle of Simtokha Dzong resulted in a decisive victory of Ngawang Namgyal's forces, while the dzong was finished in 1631. As their own efforts to remove Zhabdrung failed, the lamas appealed for the new Tsangpa ruler, Karma Tenkyong, to launch another invasion of Bhutan to overthrow their rival. For some years, however, negotiations between the Tibetans and Ngawang Namgyal's followers took place to avoid war. These proved unfruitful, and as result the Tsangpa launched their second invasion in 1634. This led the Bhutanese to claim that the Tibetan ruler had never wanted peace and that the negotiations had been a mere stragetic ploy. King Karma Tenkyong's exact motives for the invasion remain unclear, however, with Karma Phuntsho speculating that he either wanted to capture Zhabdrung, destabilize his rule in Bhutan, or obtain revered Tibetan relics that were in Bhutanese possession. In any case, the new invasion appears to have been much larger and better prepared than the one of 1619.