The Portraits of Periodical Offering () were tributary documentative paintings (with illustration on each of the portrait) produced by various Chinese dynasties and later as well in other East Asian dynasties, such as Japan and Vietnam. These paintings were official historical documents by the imperial courts. The term "" roughly translates to "duty offering pictorial". Throughout Chinese history, tributary states and tribes were required to send ambassadors to the imperial court periodically and pay tribute with valuable gifts (; gòngpǐn). Drawings and paintings with short descriptions were used to record the expression of these ambassadors and to a lesser extent to show the cultural aspects of these ethnic groups. These historical descriptions beside the portrait became the equivalent of documents of diplomatic relations with each country. The drawings were reproduced in woodblock printing after the 9th century and distributed among the bureaucracy in albums. The Portraits of Periodical Offering of Imperial Qing by Xie Sui (), completed in 1751, gives verbal descriptions of outlying tribes as far as the island of Britain in Western Europe. Portraits of Periodical Offering of Liang (526–539 CE) The Portraits of Periodical Offering of Liang () was painted by the future Emperor Yuan of Liang, Xiao Yi (ruled 552–555 CE) of the Liang dynasty while he was a Governor of the Province of Jingzhou as a young man between 526 and 539 CE, a post he held again between 547 and 552 CE, and had the opportunity to meet many foreigners. It is the earliest surviving of these specially significant paintings. They reflect foreign embassies that took place, particularly regarding the three Hephthalite (Hua) ambassadors, in 516–520 CE. The original of the work was lost, but three copies or derived works are known. Portraits of Periodical Offering of Liang (526–539 CE) (Song dynasty copy of the 11th century CE) A surviving edition of this work is a copy from the Song dynasty in the 11th century, the Song copy of the Portraits of Periodical Offering of Liang (), and is currently preserved at the National Museum of China. The original work consisted of at least twenty five portraits of ambassadors from their various countries. The copy from the Song dynasty has twelve portraits and descriptions of thirteen envoys; the envoy from Dangchang has no portrait. The work included individual descriptions, which follow closely the dynastic chronicle Liangshu (Volume 54). The envoys from right to left