Chao (monarchy)

Chao () is a title of the Lan Na royal family members.
Chao Har Kan.
"Chao Har Kan" (เจ้าห้าขัน, lit: 'Five lords') is the style for high ranking royalty in each Lan Na state.
After the fall of the absolute monarchy, the Chao har kan system was abolished by the People's Party (Khana Ratsadon - คณะราษฎร). 
Today, all of the "Chao" family use "na Chiangmai", "na Lamphun", and "na Lampang" as their surname.