Thanks for your reply.
On the facts, assuming she makes her application for a spouses visa from Japan once you are married then the previous deportation order that she was issued upon attempting to enter the UK as a visitor is unlikely to affect her application.
The UKBA may rejected it initially, thought in my view would be very unwise to do so, in which case you would have to appeal and would probably win arguing Article 8 rights Human Rights Act 1998 (right to family and private).
She will have to apply for a spouses visa once you are married to the British Embassy nearest to her and show:-
1. That you are legally married to eachother (marriage certificate)
2. That you are present and settled in the UK (property records - tenancy agreements, Land registry office copies, other records of your life here, council tax bills etc.
3. You have met before (statements, correspondence)
4. Your decision to marry was not due to you potentially being deported)
5. You intend to live permanently together here in the UK as husband and wife (statements, evidence of her (statements about your relationship from you both and any others, correspondence)
6. You can support each other withoutthe need for public funds (bank statements, evidence of income, evidence of jobs available that your husband could do)
7. You have suitable accomodation which is owned or lived in only by you or your household and where you and your dependents can live without any help from public funds (tenancy agreement, land registry docs if you your own home)
8. That neither of you are younger than 21 years of age. (birth certificates, passports)
You will need to apply for settlement (ie. spouses visa) by using VAF4 Settlement, available for download from UKBA's website. It would be best for either a solicitor in the UK to prepare it in consultation with both you and your wife before submitting it.
She will also have to pass the English language test to show she has a basic command of listening/spoken english. Very basic everyday phrases and she can contact the embassy to get a list of approved test providers.
You can find Uk immigration solicitors through the following Law Society Website search engine:-
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