Buddhism was at its peak during the Tang Dynasty and as a result after three hundred years of political unrest, China was reunified. Buddhist monasteries acquired great amounts of wealth in the form of land, grains, and precious metals. Buddhism gained much popularity amongst the Tang rulers. Emperor Gaozong honored the famous monk Xunazang for his journey to India to gain more knowledge on the Buddhist sutras. Empress Wu, the only empress in all of Chinese history, also favored Buddhism. She tactfully used Buddhism to weaken her opponents. Sadly, Buddhism began to lose its influence with the decline of the Tang Dynasty.