Origins of the Lan (兰) surname
Chinese sources record 8 separate lines of origin for the Lan (兰) surname. Each is summarised below with its source.
Originated from the Ji (姬) surname (a concubine-born son of Duke Mu of Zheng)
During the Spring and Autumn period, Duke Mu of Zheng (Zheng Mu Gong, 郑穆公) was named Zi Lan (子兰); his concubine-born children adopted the character 'Lan' (兰) from their father's given name as their surname, forming one branch of the Lan (兰) surname.
Originated from the Mi (芈) surname (the youngest son of King Zhuang of Chu)
During the Spring and Autumn period, the youngest son of King Zhuang of Chu (Chu Zhuang Wang, 楚庄王) was named Zi Lan (子兰); his concubine-born descendants also adopted 'Lan' (兰) as their surname, constituting another origin of the Lan (兰) surname.
Adopted from a fief name (Lan Yi, a fief in the State of Chu)
During the Spring and Autumn period, a high-ranking minister was enfeoffed at Lan Yi (兰邑), a fief of the State of Chu (Chu Guo, 楚国), located in present-day Zaozhuang (枣庄), Shandong Province; his descendants later adopted 'Lan' (兰), the name of the fief, as their surname.
Surname derived from Hui ethnic group transliteration
During the Yuan dynasty, the official Anduca (谙都刺) had his name transliterated into Chinese as 'Lan' (兰); his descendants adopted this transliterated name as their Han Chinese surname.
Sinicized Xiongnu surname
During the Sixteen Kingdoms period of the Five Hu era, the Lan (兰) surname was one of the four prominent Xiongnu surnames in the Han State (Han Guo, 汉国), originating from the sinicization of a minority ethnic surname.
Sinicized surnames from other ethnic groups
The Lan (兰) surname is found among the Yi (彝族), Tujia (土家族), Manchu (满族), Zhuang (壮族), Yao (瑶族), Mongol (蒙古族), Russian (俄罗斯族), and She (畲族) ethnic groups; in most cases, it derives from the sinicization of native surnames.
Name change from Lan (蓝) to Lan (兰) to avoid punishment
Some Lan (兰) families in Mengshan County (蒙山县), Guangxi Province, originally bore the surname Lan (蓝) but voluntarily changed it to Lan (兰) due to ancestral criminal conviction.
Name change caused by erroneous use of the 'Second Simplified Chinese Characters'
In contemporary times, due to the promotion of the 'Second Simplified Chinese Characters' (Er Jian Zi, 二简字) and everyday misusage, the character 'Lan' (蓝) was mistakenly simplified to 'Lan' (兰), causing some people with the surname Lan (蓝) to be erroneously registered as Lan (兰); government authorities did not correct this error.