Lan is the Mandarin pinyin and Wade–Giles romanization of the Chinese surname written 兰 in simplified Chinese and 蘭 in traditional Chinese. As of 2008, it is the 154th most common surname in China, shared by 840,000 people. Lan 蘭 is not listed in the Song dynasty classic text Hundred Family Surnames. The people of the Xiongnu Lan (tribe) assimilated into Han Chinese culture and were given the surname Lan. Source: Wikipedia (en)