In late Medieval China, depending on the kingdom, one knew at least written Classical Chinese, spoken Middle Chinese, Khitan, Tangut, plus (Southern Song) Miao, Viet, likely Khmer too etc. 2/x

In SE Asia the lithurgical Pali and Sanskrit knowledge was likely widespread among the (too many) mueang, plus Vietnam ad access to Classical Chinese and Middle Chinese. Heavy multilinguism was common among the "mountain people" like Karen, Kayah, Hmong etc. 3/x