Collecting the birth & marriage certificates

One of the most arduous paperwork processes for naturalization is the collection of birth, death, divorce, adoption, and marriage certificates for your family. It's tough paperwork to get because most likely you are in Japan, and most likely that paperwork is overseas. Because that paperwork is often decades old, most family members are not in possession of it and have moved or are living in a place far away from the local government office which holds their records. This means that in addition to you needing to contact your family, your family members will probably need to apply, via mail, to retrieve copies of their records. A paper chain relay, if you will. You will also need your own birth (hopefully not death), and possibly marriage, adoption, or divorce certificates, so you can empathize with your family members' paperwork pain.

Why does Japan need these certificates?

All Japanese citizens either have or belong to a 戸籍 {koseki} (family register), which tracks Japanese families and their relationships. Your spouse, your parents, and your children will all be on it. Thus, to construct a brand new family register for a naturalized person, they need this family information.

A secondary reason why this documentation is needed is to verify whether or not you qualify for any of the conditions for 簡易帰化 {kan'i kika} (simplified naturalization).

Whose certificates do they want?

They don't want your family history back to the beginning of time. They want your immediate family. No grandparents, in-laws, cousins, or nephews/nieces or uncles/aunts are needed. I only needed to get my parent's marriage certificate, not my sibling's.

It's a good thing that they only wanted my immediate family; they're pretty boring and by-the-numbers when it comes to genealogy and relationships. Once you look back a few generations, my family history gets very, very complicated. I imagine this has caused a lot of hair pulling with other candidates that have much more complicated family trees.

Other than your 源泉徴収票 {gensenchōshūhyō} (Japanese tax withholding statement) and your 特別区民税通知書 {tokubetsu kumin zei tsūchisho} (Japanese special munipicial tax notice), these documents will probably be the only ones not on standard A4 paper, so they're going to mess up your document stack from the perspective neatly stacking, collating, and filing. Due to the era in which the documents were made, they may be filled out with a typewriter (as was the case with my American paperwork), or even handwritten in cursive (!) (my British paperwork).

Translating

All of the non-Japanese certificates must be translated (on A4 paper, regardless of the original's paper size). I simply inputed all of the text of the certificates into a web based translation service, hand-edited the results to make them sane and comprehensible, and added the translator's name — me, the date, and my address on each translation. You don't need to do anything fancy like embed the Japanese into the original English/foreign text formatting or try to perfectly mimic the layout of the foreign document.

If you do use machine translation, and you're careless and don't proofread and after-edit the documents and overlook some wacky translations, it's possible they won't accept them.

Additional Paperwork

Many states do not provide paperwork that proves that a women only gave birth to a certain number of children. Because Japan doesn't want anybody omitted, you may need to provide your mother with the following form (which is in Japanese, on A4 paper), have her complete it, sign it, and return it to you for submission with your packet:

申述書 {shinjutsusho}
(statement)

私と＿＿＿＿＿＿＿＿＿との間に生まれた子は、下記のとおりです。 {watashi to ＿＿＿＿＿＿＿＿＿ to no aida ni umareta ko wa, kaki no tōri desu.}
(I gave birth to the children listed below with ___________________.)

氏名 {shimei} (name)	続柄 {tsuzukigara} (relationship)	生年月日 {seinengappi} (birthdate)	出生地 {shusseichi} (birth place)

年 {nen}　　月 {gatsu}　　日 {nichi}
(year-month-date)

住所 {jūsho}　　　　　　　　　　　　　　　　　　　　　　　
(address)　　　　　　　　　　　　　　　　　　　　　　

氏名 {shimei}　　　　　　　　　　　　　　　　　　　　　　　
(name)　　　　　　　　　　　　　　　　　　　　　　　
印 {in}　
(seal)　

The "relationship" column should say whether they were the first, second, third, etc., son or daughter. The "with _______" should have the name of the biological father. The "seal" should have the mother's signature if she doesn't have an official seal (if she's not from an east Asian country).

It's okay for the mother to fill out this form in English — as opposed to 仮名 {kana} (Japanese syllabet). It's also okay to give her a completed translated version of this form for her to sign then re-translate it back after receiving it.