7. What is the legal concept of "domicile"? How do I know if my domicile is Hong Kong?
"Domicile" is a legal concept that is recognised by common law. It refers to the country (or division within a country) from which a person originally comes or, if he or she has abandoned that place in favour of another, the new country or jurisdiction. Domicile is different from nationality and permanent residence, although for most people their place of domicile is the same as their place of nationality or residence.
Domicile (sometimes spelt "domicil") may affect matters of marriage, divorce and inheritance of a deceased person's property. This is because, under the rules of private international law, the Hong Kong courts defer to the law of the place of domicile of a person in certain circumstances. For example, if a person dies in Hong Kong but was domiciled somewhere else at the time of death, then the law of the place of domicile may determine the manner in which the deceased person's property is allocated.
In some countries the place of domicile may affect tax liability.
In reply to the second question, if your ancestral roots are in Hong Kong, then you are probably domiciled in Hong Kong unless you have migrated to another place and made a decision never to live in Hong Kong again.
If you come from a place other than Hong Kong, you probably acquired a domicile of origin at birth from that place, whether it was Mainland China or another country. However, you may have acquired a domicile of choice in Hong Kong if you have settled here permanently without any intention to return to live in your place of origin.
The law of domicile is very complex. Advice should always be sought from a lawyer with expertise in this area whenever questions about place of domicile arise.