Huanglan 皇覽 "Imperial overview" was China's oldest encyclopaedia. It was compiled during the Wei period 曹魏 (220-265) by Liu Shao 劉劭, Wang Xiang 王象, Miao Xi 繆襲, Huan Fan 桓范, and Wei Dan 韋誕 and comprised more than a thousand chapters. Liu Shao is known as the author of the Renwuzhi 人物志, a book on the human character. The Huanglan was compiled on imperial order and finished in 222, just two years after the inthronisation of Emperor Wen 魏文帝 (r. 220-226, Cao Pi 曹丕).
The book was intended to provide the emperor with the complete knowledge of his time. It was divided into fourty-odd parts, each of which was divided into a dozen of subchapters. The book as a whole is lost, but it is known that during the Liang period 梁 (502-557) there were still 680 juan existing, but during the Sui period 隋 (581-618) a mere 120 juan. It might be that some manuscripts of the encyclopaedia were just extracts, and the original went lost in contrast to these more handy versions. He Chengtian 何承天, for instance, had compiled a 123 juan-long version during the Liang period that was revised by Prince Xiao Chen 蕭琛 under the title Huanglao chao 皇覽抄 (with a length of 20 juan), as said in the imperial bibliography Jingjizhi 經籍志 in the official dynastic history Suishu 隋書. The bibliography in the history Jiutangshu 舊唐書 speaks of two manuscripts, one compiled by Hen Chengtian, and one by Xu Yuan 徐爰. A kind of index called Huanglan mulu 皇覽目錄 with a length of 4 juan is likewise lost. The Huanglan served as a model and blueprint for the encyclopaedia Sibu yaolüe 四部要略, compiled during the Southern Qi period 南齊 (479-502) by Xiao Ziliang 蕭子良 and the Tang-period 唐 (618-907) encyclopaedia Yiwen leiju 藝文類聚, which survives as a whole.
During the Qing period 清 (1644-1911), several scholars collected surviving fragments of the text. Xun Fengji 孫馮翼 reconstructed the chapters Yili 逸禮 and Zhoumuji 塚墓記. His reconstructions are to be found in the series Wenjingtang congshu 問經堂叢書 and Congshu jicheng 叢書集成初編. Huang Shi 黃奭 collected fragments that were published in the series Han-Wei congshu 漢學叢書 under the name Wei Huanglan 魏皇覽. The same fragment collection is also to be found in Huang Shi's collected works Huangshi yishu kao 黃氏逸書考. Wang Mo's 王謨 reconstruction Huanglan Yili 皇覽逸禮 is included in the collection Han-Wei yishu chao 漢魏遺書鈔.