yes, in vietnam, the students were required to pass imperial exams. and this exam was said fkcing hard. only few passed. I found this article below on the internet. only the bests of graduates were chosen to be sent as envoy to Chinese emperors.
Trạng Nguyên (状元) is the title given to ones who passed the imperial examination with highest mark in Vietnam feudal dynasty of Ly, Tran, Le, Mac. In order to get this title, you generally have to pass 3 exams called : Hương, Hội and Đình.
The first examination was opened in 1075 under Ly dynasty and the first guy who was given this title is Lê Văn Thịnh .There are 3 highest titles called : Trạng Nguyên, Bảng Nhãn and Thám Hoa.
However, Nguyen DYnasty stopped the imperial examination in 1919 and also the title Trạng NGuyen was abolished in Nguyen dynasty therefore the last guy who owned this title is Trịnh Tuệ ( 1736) during Le-Trịnh period. Through 184 examinations until 1919, there are 2785 Confucious scholars pass the exams and given various titles regarding to their marks and there are only 56 Trạng Nguyên. When they passed, their names were carved on the honor stele in Temple of Literature in Hanoi.
And example of a stele :
It has introduction, names of ones who passed the exams and their duty to the country.
Names :
First Class:
PHAN KÍNH 潘 敬 : Ha Tinh province
Second class :
TRẦN VĂN TRỨ 陳 文 著 : Hai Duong province
Thirld class :
LÊ HOÀNG VĨ 黎 黃 瑋 : Ha Tay province
NGUYỄN HOẢN 阮 完 : Thanh Hoa province
PHẠM SĨ THUYÊN 范 仕 銓: Hung yen province
LÊ DOÃN GIẢN 黎 允 僩: Bắc Ninh province
LÊ DOÃN GIAI 黎 允 佳: Thanh Hoa province.
There are 82 steles out 114 stele remain until today.