They would purchase books published in China with Chinese characters to take back to European courts and libraries and just assumed they were the one written "Chinese language" and were so classified. How many volumes are sitting libraries that are erroneously thought to be works in Mandarin but which are actually written in other Han languages?
Many scholars read the word 官音 "kuan-yin" and translate it "Mandarin" instead of "court language." And then by Mandarin, they are actually thinking of this modern language used in Beijing and adopted as a national language in the 1900s. They seem not to account for the rise of fall of different dynasties, not to mention annexation by foreign empires (like the Mongols and Manchus) with totally alien languages. Would these new elites not completely alter the languages used at court just as William the Conqueror's Normans brought their own French language with them to England in 1066? Is the language used by the Manchu court, "Qing Dynasty," so similar to the Ming before it? How about the Mongol Khanate "Yuan Dynasty" before it? Surely these two foreign empires significantly altered pronunciation and word usage if not radically changing everything about the court languages in use of predecessor empires. One wonders whether so called "dialects" especially spoken in the south are not actually former court languages of prior dynasties whose refugees fled the new empire's minions.
This same bias towards the prestige language of Mandarin in Taiwan has left the next generation thinking there is no written form for their mother tongues whether Hakka, Holo Taiwanese, or the Aboriginal languages. Though they are literate in Mandarin, they are left illiterate in the language their grandparents speak at home. And also the ethnic Han elitism -- that considers an alphabetic script to be somehow merely a pronunciation aid instead of written words when compared with Chinese characters -- causes written works of these languages that used romanized phonemes to be basically dismissed as non-literature.
Following is a catalogue of works published in written Holo Taiwanese using the POJ romanization system. None of it is taught in the schools as part of Taiwan's literary heritage. Additionally, there is some scholarly work done on some printed books using Chinese characters in the 1600's -- mostly compilations of arias and plays -- that are actually written Holo Taiwanese using Han characters. Some of these books made their way to libraries in the Netherlands and England. You can actually purchase reprints of the works in a book published by SMC Publishing titled, The Classical Theatre and Art Song of South Fukien by Piet Van Der Loon, an Emeritus Professor of "Chinese" from Oxford University.
1. Compilations of periodical: Tâi-oân-hu-sian Kàu-hōe-po (Taiwan Prefectural City Church News) from July 1885 through 1970
[These can be read at the 7th Floor Library of the General Assembly Office of the Presbyterian Church in Taiwan: No. 3,Lane 269, Roosevelt Road, Sec.3, Taipei,106 TAIWAN]
2. “Pit Soàn ê Chho. Ha'k” (Fundamental Mathematics) by Ui-lim Ge in 1897 [ 筆算的初學 … 倪為林 ]
3. “Lāi Gōa Kho Khàn-hō.-ha'k” (The Principles and Practice of Nursing) by George Gushue Taylor in 1917 ( 內外科看護學…戴仁壽 醫師)
[Chapter 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40]
4. the novel “Chhut Sí Sòaⁿ” (Line between Life and Death) by Khe-phoan Teⁿ in 1926
5. the collection of commentaries “Cha'p-hāng Koan-kián” (Opinions on Ten Issues) by Poe-hoe Chhoa in 1925
6. Compilations: Taibun periodicals such as Tâi-bûn Thong-sìn (台文通訊)
7. Compilations: Tâi-bûn Bāng-Pò (台文罔報) -- also uses Pe'h-oē-jī as the romanization for writing Taiwanese
8. This volume: --- " 5%台譯計劃.
In November of 1995, some Taiwanese youths who were concerned about the writing of Taiwanese decided to deal with the Taiwanese modernization and loanwords through translation from foreign language into Taiwanese. The organization 5% Project of Translation in Taiwanese was then established on February 24, 1996. It's members have to contribute 5% of their income every month to the 5% fund. The first volume includes 7 books. They are Lear Ông, Kui-a Be-chhia, Mi-hun-chhiun e Kui-a, Hoa-hak-phin e Hian-ki, Thin-kng Cheng e Loan-ai Ko.-su, Pu-ho.-lang e Lek-su, and Opera Lai e Mo.-sin-a, published by Tai-leh (台笠) press in November 1996."
- (Src: "Romanization and Language Planning in Taiwan" -Wi-vun Taiffalo Chiung)
Good Links regarding Written Taiwanese:
Siá Tâi-oân ê Oē