A hong (Chinese: 行; pinyin: háng; Jyutping: hong4-2) originally designates both a type of building and a type of Chinese merchant intermediary in Guangzhou (formerly known as Canton), Guangdong, China, in the 18–19th century, specifically during the Canton System period.
The name hong (Chinese: 行; pinyin: háng; Jyutping: hong4; lit. 'profession, also row') originally referred to the row of factories built outside of the city walls of Guangzhou 广州 (Canton), near the Pearl River. The Thirteen Factories were used during the Canton System period to host foreign traders and the products purchased, under the aegis of the cohong. The Hong (or Factories) were usually owned by hong merchants such as Pan Zhencheng (Poankeequa 1).
The Guangzhou Hong changed location several times after fires, and became less important after the First Opium War (1839–1842), as Guangzhou lost its monopoly of foreign trade and Hong Kong was ceded to the British as a colony.
In Hong Kong, the name hong designated major business houses. One of the earliest foreign hongs established in Hong Kong was Jardine Matheson & Co., who bought Lot No. 1 at the first Hong Kong land sale in 1841. In 1843 the same firm established a mainland China headquarters on the Bund in Shanghai, just south of the British Consulate. The building was known as "the Ewo Hong", or "Ewo House", based on the Cantonese pronunciation of the company's Chinese name (怡和行, Cantonese: Yiwo Hong, now 怡和洋行). Jardines took the name from the earlier Ewo hong run by Howqua near Whampoa, Canton.
The term is most often used in reference to Colonial Hong Kong companies directly.
Prior to the establishment of banking institutions other than small foreign bank branches, the three firms that financed most of Hong Kong's economic activities were Jardine's, Dent's and Russell's. Most of these firms became multinational corporations with management consisting of mostly European expatriates.
By the time of the handover of Hong Kong to China in 1997, many of the hongs had diversified their holdings and shifted their headquarters offshore away from Hong Kong to avoid potential takeover by the Chinese Communist Party.
Note: Below are lists of companies that had a predominant effect on Hong Kong's economy at a particular era. Their noteworthiness is debatable. The official names of the era are used.