Take a stroll through a Japanese city, and you’ll come face to face with any number of loan words from non-Japanese languages. Some you’ll experience visually, written out in the katakana phonetic characters often employed for foreign-originating words. カフェ (kafe, cafe), レストラン (resutoran, restaurant), and the hybrid パン屋 (pan-ya, bakery) stick out among many more. Stores plaster leaflets proclaiming their search for スタッフ (sutaffu, staff), and advertise their current キャンペーン (kyanpeen, sales campaigns). Conversations you happen to overhear contain even more foreign loan words; people talk about favorite celebrities using words like アイドル (aidoru, “idols”) and タレント (tarento, “talents”).
And in the background, two more loanwords ring out, so ubiquitous that you can easily forget their non-native origins. Children call out to their parents using two very standard words: ママ (mama) and パパ (papa).
The words we use to refer to our parents are an interesting thing. This is something language learners who have tried their hands at mastering different tongues will doubtless have noticed: parental nomenclature tends to bear a phonetic resemblance between different languages, including some that are quite unrelated to each other. In fact, “mama” and “papa” occur as parental names throughout the world, often by chance or by dint of ease of linguistic development. Japanese, however, is not one such case. Here, these specific words entered rather late, usurping older familial terms. Once ingrained, even the wartime Japanese government’s attempt to enforce a ban on foreign words wasn’t enough to stop them. “Mama” and “papa” were here to stay.
Mama and Papa Through Space and Time
Why do “mama” and “papa” and similar words pop up in such disparate locations and historical periods? It’s tempting to see the words as some primordial root descending back to humankind’s first languages. But while it is quite possible that Neanderthals used a similar word to “mama” to address their moms, it’s not because of a shared linguistic connection. Rather, linguists say, it’s because of the sounds that babies find easiest to first pronounce.
Ah is the very easiest sound to make, since it requires no special positioning of the tongue or lips. Mmm comes naturally when making noises with your mouth closed. Combine them and you get ma, which just so happens to be one of the first sounds many babies make.
“Papa,” “baba,” and “dada” often come next, since a little experimenting with puffs of air and noise easily results in such aspirated and non-aspirated noises. When babies make these noises, parents often feel like their tiny children are trying to talk to them – and assign these sounds as self-descriptors. Once the parents start referring to themselves with these words when talking to their babies, it creates a linguistic loop, imbuing experimental babbling with meaning. Thus, “mama,’ “papa,” “baba,” and “dada” pop up all over the linguistic world in various iterations. 
Far afield from Japan, innumerable languages have developed separately to have similar-sounding words for close familial relations. In Hebrew, “father” is “abba” – it’s unsurprising that closely related Semitic language Arabic has “Ab” as “father.” (Plus “baba,” so close to “papa” as another word for dad.) Much farther away, in Mongolia, “father” is the linguistically similar “aav.” Hungarian, a Uralic language likely hailing from the Ural mountains, has “apa” for the same. These are just a smattering of similar examples from very different language families.
Parental Japanese Through the Ages
If “mama” and “papa” aren’t words local to Japan, then just how did children refer to their parents before the terms arrived? Well, the first answer is a pretty obvious one to anyone who speaks modern Japanese. Like languages the world over, there are numerous words in Japanese for parents, running the gamut of both childishness and stately formality. Unlike a language akin to, say, English, Japanese additionally distinguishes between words used for one’s own parental figures and those of others.
The most basic form of home-grown parental terminology is haha (母) for mommy, and chichi (父) for daddy. Those two kanji characters form the basis of most of the vast range of terms used for mothers and fathers. Pick up a Japanese textbook, and some of the first vocab you’ll encounter will include those kanji: お母さん (okaasan, mother) and お父さん (otousan, father). These last two are formal words, used not only for one’s own parents but for parents-in-law, as well as other people’s parents.
Chichi is a compounding of the ancient word chi, which seems to have been an honorific term for a male; perhaps, even earlier, it derived from homonyms meaning “blood,” “soul,” or, confusingly, “breast.” Numerous male relations take on the same kanji: 祖父 (ooji, grandfather); 叔父 (oji, uncle), and more. You can also call your dad 親父 (oyaji), which combines the characters for “parent” and “father.” These days, the word has an affectionate connotation, like “pops” or “old man.” Then there’s toto, an infantile pronunciation of chichi, from whence came the more respectful 父様 (toto-sama), and, eventually, the modern お父さん (otousan) you learned from your first year JPN textbook.
There are various theories as to the origins of haha, mommy. One is quite complex, with the word originating as an infantile mispronunciation of more formal samurai-era terms for mother/wife. In this version, both haha and okaasan derive from the archaic 御方様 (okatasama, mother/wife). Perhaps it’s easier to imagine haha came first, leading to the numerous other words for mother; hawa, kaka, kakasama, kaasan, hahaoya. 
Another common word for one’s mom, although perhaps a bit old-fashioned, is お袋 (ofukuro), literally “honorable bag.” In function, it’s the motherly equivalent of oyaji. The word first appears in the Muromachi Period (1336 to 1573), when it was mostly used by daughters when talking to their mothers – these days, it’s mostly sons who use it. Theories abound as to the term’s origin. Perhaps it refers to mothers’ household management and organizational skills; perhaps it’s an oblique reference to the womb; it may also be a corruption of the word futokoro, meaning the gap between kimono and breast where babies were often swaddled.
Linguistic Give and Take
So, we have a good two thousand years of linguistic evolution for Japan’s own paternal and maternal terms. In addition to all of the above, there’s also uncountable local and archaic words; at different times and places, 父 was read as tete, kazo, kaso, shishi, ate, and more. 母 has been omo, iroha, and amo. There’s still semi-archaic formal words like 母上 (hahaue) and 父上 (chichiue). And this is just discussing Japanese itself; of course, indigenous vocabularies like the various Ryukyu and Ainu languages have their own words. (If you’re wondering, Okinawan “mom” is “Anmaa,” and in Ainu it can be “Unu.”)
But then came those pesky Europeans.
Japanese is already made up in considerable percentage of Sinitic words of Chinese origin; the first encounter with European languages came in the late 1500s, with early interactions with the Portuguese. Before long, the Dutch became the main point of contact. However, the spread of loan words through the archipelago was stymied by the Tokugawa shogunate‘s policy of strict isolation (sakoku).
Loaned Out Parents
This all ended in the early 1850s. US Commodore Matthew Perry’s forceful “opening of Japan” led to sudden mass interaction with the European world; after the Shogunate fell and feudalism was abolished, the new oligarchic leaders of the country rushed headlong towards westernization. European clothing, architecture, political structures, education – all manner of societal changes happened nearly overnight. A few of these elites of the Meiji era (1868-1912) even hoped to replace Japanese and make English the official language.
Nothing quite so drastic occurred, thankfully. (Although there was a major standardization of Japanese itself during Meiji.) Instead, there occurred a natural linguistic exchange, although one heavily weighted towards the borrowing of European words. “Mama” and “papa” came in via the upper echelons of late Meiji society. Until mere decades earlier, traveling abroad had been banned on pain of death; now, Japanese diplomatics and businessmen were traveling the world. The scions of wealthy Japanese families were studying at Oxford and Yale. Japanese children were being born abroad – and when such families returned, they brought back “mama” and “papa,” too.
Hearing their children use these foriegn words delighted many of the “high collar” parents of late Meiji. A fad ensued, with upper-class parents, the fathers now dressed in western suits, encouraging their young children to call them by their European monikers. It was in the early Taisho period (1912-1926) that the words filtered down to everyday people in Japan. By the early prewar era, “mama” and “papa” were firmly engrained in the Japanese childhood lexicon.
A War of Words
Meiji-era aristocrats were generally enthusiastic about just about everything “modern”: read, “Western.” By the 20th century, however, there were already those for whom the complete upending of older Japanese culture had gone too far. As tensions rose in the late 1920s and jingoistic ’30s, there was an about-face, and anything too culturally “foreign” became a target for suspicion.
The famed poet Takahama Kyoshi (高浜 虚子) was one who disparaged the foreign takeover of parental names. The word papa, he said, “sounds like it would be sent flying if you blew on it.” Parents were still to be respected in those times, with strict levels of formality used between children and their elders. These foreign words sounded weightless; overly friendly. Takahama even engaged in a “Papa-Mama Debate” in 1917; his interlocutor, the noted feminist poet Yosano Akiko (与謝野 晶子), had other ideas. “Japan’s syllabary and laws are all transplants from abroad,” she said. “There’s no special reason to dest such words.”
A Threat to the Social Fabric?
In 1934, the first attempt to ban the words took place. It came from the highest echelons of the Japanese government. Matsuda Genji, Minister of Education of the Okada cabinet, had been visiting a local elementary school when, to his horror, he discovered the studentry using foriegn words to refer to their esteemed parents. He reportedly flew into a rage. Soon thereafter, he gave a furious speech on the topic. “Recently, there has been a fad for the words ‘papa’ and ‘mama.’ Alas, the filial piety of Japan, known from time immemorial, is in the process of being lost to us. Let us exterminate these words forthwith!” 
The Western press had a field day. Matsuda was already the subject of some ridicule, having compared himself to the esteemed Prince Saionji; he’d even once referred to himself as “the Lloyd George of East.” The Times called him “Braggat Matsuda,” pointing out that:
Perfectly good Japanese today are such words as “club”, “kodak,” “beefsteak” (pronounced bifteki) and the whole argot of baseball from “foul” to “home run.”(Monday, Sep. 10, 1934). JAPAN: Not Papa, Not Mama. The Times.
Here to Stay, and to Say
Matsuda passed only two years on since his push to outlaw “mama” and “papa.” The words, however, only came under closer scrutiny as the Pacific War loomed. The Times may have mocked him for fighting against the linguistic tide, but within a scant few years of Matsuda’s death, the jingoism had reached such a fevered pitch that most of the loan words mentioned were banned. During the war years, anything that smacked of the enemy was to be avoided at all costs. To this day, those English baseball terms mentioned by the Times are in disuse in favor of Japanese creations; all thanks to wartime linguistic self-censorship.
However, it’s one thing for adults to be cognizant of the social danger a word poses and avoid its use. For children, such abstractions don’t come quite so easily. The imperial government may have wanted a purely Japanese lexicon used by the families of Japan, but a state’s reach only goes so far. “Mama” and “papa” survived the war, and are still with us in Japan to this day. As an Asahi Shimbun article put it in 2004:
The words spread all the more during the post war years. These days, it would appear that even the Crown Prince’s own family has joined the “Papa” Faction.”(2004年10月15). 朝日新聞.
And that, kids, is how Japan met your “mama.”
What to Read Next:
 Mcwhorter, John. (10/12/2015). Why ‘Mom’ and ‘Dad’ Sound So Similar in So Many Languages. The Atlantic.
 コラク. (12.11.21). 父（ちち）・母（はは）の語源の考察. コラクのブログ.
 お袋／おふくろ. 語源由来辞典
 (2006/10/25). 日本語のママ・パパの起源は意外に古い. Travellers Tales.