Question: When did Northern Rhodesia gain independence?
About the article "Victoria Falls", section "Zambia's independence and Rhodesia's UDI".

Candidate passages:
The state comprised the former self-governing (since 1923) Colony of Southern Rhodesia and the British protectorates of Northern Rhodesia, and Nyasaland.
The Federation officially ended on 31 December 1963, when Northern Rhodesia gained independence from the United Kingdom as the new nation of Zambia and Nyasaland gained independence as the new nation of Malawi.
Southern Rhodesia then became known as Rhodesia and is now Zimbabwe. 
 The Southern Rhodesian government announces that, when Northern Rhodesia achieves independence as Zambia, the Southern Rhodesian government will officially become known as the Rhodesian Government and the colony will become known as Rhodesia.  
On 7 October 1964 the Southern Rhodesian government announced that when Northern Rhodesia achieved independence as Zambia, the Southern Rhodesian government would officially become known as the Rhodesian Government and the colony would become known as Rhodesia.
On 23 October of that year, the Minister of Internal Affairs notified the Press that the Constitution would be amended to make this official.
The Legislative Assembly then passed an Interpretation Bill to declare that the colony could be referred to as Rhodesia.
The Bill received its third reading on 9 December 1964, and passed to the Governor for assent.
However, no assent was granted to the Bill.
Section 3 of the Southern Rhodesia (Annexation) Order 1923 provided that Southern Rhodesia "shall be known as the Colony of Southern Rhodesia" and the Southern Rhodesia (Constitution) Act 1961 and the Order-in-Council which followed it both referred to it as such.
These were United Kingdom measures and it was outside the powers of Southern Rhodesian institutions to amend them.
The Rhodesian government, which had begun using the new name anyway, did not press the issue.
The Unilateral Declaration of Independence was in the name of Rhodesia.
While the new name was widely used, 'Southern Rhodesia' remained the colony's formal name in United Kingdom constitutional theory: for example, the Act passed by the United Kingdom Parliament declaring the independence a legal nullity was entitled the Southern Rhodesia Act, 1965.
When the rebellion was formally declared at an end by the passing of the Constitution of Zimbabwe-Rhodesia (Amendment) (No.
4) Act 1979, the United Kingdom resumed the governance of the colony under the direct control of the Governor, using the name of Southern Rhodesia. 
Southern Rhodesia (renamed Zimbabwe in 1980) was a special case in the British Empire.
Although it was never a dominion, it was treated as a dominion in many respects.
Southern Rhodesia was formed in 1923 out of territories of the British South Africa Company and established as a self-governing colony with substantial autonomy on the model of the dominions.
The imperial authorities in London retained direct powers over foreign affairs, constitutional alterations, native administration and bills regarding mining revenues, railways and the governor's salary.
Southern Rhodesia was not one of the territories were mentioned in the 1931 Statute of Westminster although relations with Southern Rhodesia were administered in London through the Dominion Office, not the Colonial Office.
When the dominions were first treated as foreign countries by London for the purposes of diplomatic immunity in 1952, Southern Rhodesia was included in the list of territories concerned.
This semi-dominion status continued in Southern Rhodesia between 1953 and 1963, when it joined Northern Rhodesia and Nyasaland in the Central African Federation, with the latter two territories continuing to be British protectorates.
When Northern Rhodesia was given independence in 1964 it adopted the new name of Zambia, prompting Southern Rhodesia to shorten its name to Rhodesia, but Britain did not recognise this latter change.
Rhodesia unilaterally declared independence from Britain in 1965 as a result of the British government's insistence on majority rule as a condition for independence.
London regarded this declaration as illegal, and applied sanctions and expelled Rhodesia from the sterling area.
Rhodesia continued with its dominion-style constitution until 1970, and continued to issue British passports to its citizens.
The Rhodesian government continued to profess its loyalty to the Sovereign, despite being in a state of rebellion against Her Majesty's Government in London, until 1970, when it adopted a republican constitution following a referendum the previous year.
This endured until the state's reconstitution as Zimbabwe Rhodesia in 1979 under the terms of the Internal Settlement; this lasted until the Lancaster House Agreement of December 1979, which put it under interim British rule while fresh elections were held.
The country achieved independence deemed legal by the international community in April 1980, when Britain granted independence under the name Zimbabwe. 
The official name of the country under British law was "Southern Rhodesia", but the government in Salisbury used the shorter name "Rhodesia".
This situation dated back October 1964, when Northern Rhodesia changed its name to Zambia concurrently with its independence from Britain.
In the absence of a "Northern" Rhodesia, the colonial government in Salisbury felt the geographical qualifier "Southern" had become superfluous, and so passed legislation to formally become simply Rhodesia, but Britain refused to approve this on the grounds that the laws naming the country came under the purview of Whitehall, not Salisbury, and so could not be altered by the colonial government.
The name was therefore not changed in law.
Salisbury went on using the shortened name in an official manner nevertheless, while the British government continued referring to the country as Southern Rhodesia for years afterwards, an exercise described in 1978 by the Rhodesian lawyer J. Reid Rowland as "unrealistic and pedantic".
The British government maintained this stance regarding the June–December 1979 successor state of Zimbabwe-Rhodesia, and when Zimbabwe Rhodesia returned to colonial status from December 1979 to April 1980, it was as "Southern Rhodesia", which had remained the official name used by the British government.
Southern Rhodesia subsequently gained international recognition of its independence in April 1980, when it became the independent Republic of Zimbabwe.