Era of Fragmentation

During this period, the political unity of the Tibetan Empire collapsed following a civil war between Yumtän (Yum brtan) and Ösung (’Od-srung),[2] after which followed numerous rebellions against the remnants of imperial Tibet and the rise of regional warlords.

[3] The last king of the unified Tibetan Empire, Langdarma, was assassinated in 842 possibly by a Buddhist hermit monk named Pelgyi Dorje of Lhalung,[4][5] or other sources state he died from fright.

The Era of Fragmentation is depicted as a low point in the development of Tibetan Buddhism, with the Nyingma school's monastic orders facing persecution and internal exile.

Nyingma monasteries were alleged to have only persevered in Amdo, then largely dominated by non-Tibetan peoples and conquered by a Tibetan polity in the 10th century.

Modern historians argue that Buddhism was in fact widespread during the fragmentation period, and that local polities shared close relationships with Buddhist monastic leaders.