(1)As from the appointed day, the British Nationality Acts, 1948 and 1958, shall have effect as if—
(a)in subsection (3) of section one of the said Act of 1948 (which provides for persons to be British subjects or Commonwealth citizens by virtue of citizenship of certain countries) the word " and" in the last place where it occurs were omitted, and at the end there were added the words " and Nigeria ";
(b)in the First Schedule to the British Protectorates, Protected States and Protected Persons Order in Council, 1949, the words " Nigeria Protectorate " were omitted:
Provided that a person who immediately before the appointed day is for the purposes of the said Acts and Order in Council a British protected person by virtue of his connection with the Nigeria Protectorate shall not cease to be such a British protected person for any of those purposes by reason of anything contained in the foregoing provisions of this Act, but shall so cease upon his becoming a citizen of Nigeria under the law thereof.
(2)Subject to the subsequent provisions of this section, any person who immediately before the appointed day is a citizen of the United Kingdom and Colonies shall on that day cease to be such a citizen if—
(a)under the law of Nigeria he becomes on that day a citizen of Nigeria; and
(b)he, his father or his father's father was born in any of the territories comprised in Nigeria.
(3)Subject to subsection (8) of this section, a person shall not cease to be a citizen of the United Kingdom and Colonies under the last foregoing subsection if he, his father or his father's father—
(a)was born in the United Kingdom or in a colony; or
(b)is or was a person naturalised in the United Kingdom and Colonies; or
(c)was registered as a citizen of the United Kingdom and Colonies; or
(d)became a British subject by reason of the annexation of any territory included in a colony.
(4)A person shall not cease to be a citizen of the United Kingdom and Colonies under subsection (2) of this section if he was born in a protectorate, protected state or United Kingdom trust territory, or if his father or his father's father was so born and is or at any time was a British subject.
(5)A woman who is the wife of a citizen of the United Kingdom and Colonies shall not cease to be such a citizen under subsection (2) of this section unless her husband does so.
(6)Subsection (2) of section six of the British Nationality Act, 1948 (which provides for the registration as a citizen of the United Kingdom and Colonies of a woman who has been married to such a citizen) shall not apply to a woman by virtue of her marriage to a person who ceases to be such a citizen under subsection (2) of this section, or who would have done so if living on the appointed day.
(7)Subject to the next following subsection, the reference in paragraph (b) of subsection (3) of this section to a person naturalised in the United Kingdom and Colonies shall include a person who would, if living immediately before the commencement of the British Nationality Act, 1948, have become a person naturalised in the United Kingdom and Colonies by virtue of subsection (6) of section thirty-two of that Act (which relates to persons given local naturalisation before that commencement in a colony or protectorate).
(8)Any reference in subsection (3) or (4) of this section to a territory of any of the following descriptions, that is to say, a colony, protectorate, protected state or United Kingdom trust territory, shall, subject to the next following subsection, be construed as a reference to a territory which is of that description on the appointed day; and the said subsection (3) shall not apply to a person by virtue of any certificate of naturalisation granted or registration effected by the governor or government of a territory outside the United Kingdom which is not on that day of one of those descriptions.
(9)The protectorates of Northern Rhodesia and Nyasaland shall be excepted from the operation of any reference in subsection (4) or (8) of this section to a protectorate.
(10)Part III of the British Nationality Act, 1948 (which contains supplemental provisions) shall have effect for the purposes of subsections (2) to (9) of this section as if those subsections were included in that Act.