Question: When did the Transfer of sovereignty over Hong Kong happen?

Context paragraphs:
Flag of Hong Kong (1959–1997): The Flag of Hong Kong between 1959 and 1997 was a Blue Ensign with the coat of arms of Hong Kong on a white disk.  In Hong Kong, it is also nicknamed the Hong Kong flag (Chinese: 香港旗) or the Dragon and Lion flag (Chinese: 龍獅旗).  In 1959, following a grant from the College of Arms and with the consent of Queen Elizabeth II, it was adopted as the flag of British Hong Kong.  While the flag lost its official status following 1 July 1997 transfer of sovereignty over Hong Kong, it resurfaced in the 2010s as a symbol of protest against Chinese intervention in Hong Kong.

Consulate General of South Korea in Hong Kong: Consulate General of South Korea in Hong Kong (Korean: 주 홍콩 대한민국 총영사관 ; ), a consular mission of the Republic of Korea (ROK) to Hong Kong and Macau, is located at 5-6F, Far East Finance Center 16, Harcourt Road, Admiralty, Hong Kong.  It is one of the first South Korean overseas missions since the country's foundation, opened in British Hong Kong under approval of the United Kingdom in 1949, going through promotion and expansion in its history.  Following the Transfer of sovereignty over Hong Kong to China in 1997, the Consulate General was able to keep its presence according to a Sino-Korean agreement concerning foreign missions stationed in Hong Kong.

Hong Kong independence: Hong Kong independence () is a movement that advocates Hong Kong becoming an independent sovereign state.  Hong Kong is a special administrative region (SAR) which enjoys a high degree of autonomy under the People's Republic of China (PRC), guaranteed under Article 2 of Hong Kong Basic Law as ratified under the Sino-British Joint Declaration.  Since the transfer of the sovereignty of Hong Kong from the United Kingdom to the PRC in 1997, many Hongkongers are increasingly concerned about Beijing's growing encroachment on the territory's freedoms and the failure of the Hong Kong government to deliver "genuine democracy".

Transfer of sovereignty over Hong Kong: The transfer of sovereignty over Hong Kong from the United Kingdom to China, referred to as "the Handover" internationally or "the Return" in China, took place on 1 July 1997.  The landmark event marked the end of British administration in Hong Kong, and is often regarded as the watershed of the British Empire.

New Hong Kong Society: The New Hong Kong Society (Chinese: 新香港學社) was a political organisation existed in the early 1980s in the background of Sino-British negotiation over Hong Kong's sovereignty after 1997.  It was one of the first groups to accept Chinese sovereignty over Hong Kong and the idea of Hong Kong people ruling Hong Kong through democratic means.  The society comprised mainly young graduates who recently graduated in the 1980s and offered a detailed plan to implement the idea of Hong Kong people ruling Hong Kong in early 1983 and had discussion with the officials of the Hong Kong and Macao Affairs Office.

British Hong Kong: British Hong Kong () was the period during which Hong Kong was under British Crown rule from 1841 to 1997 (excluding the Japanese occupation from 1941 to 1945).  It was established as a Crown colony and later designated a British Dependent Territory in 1981.  Hong Kong Island was ceded to Great Britain by the Qing dynasty of China after the First Opium War (1839–42).  The Kowloon Peninsula was added to the colony after the Second Opium War (1856–60).  Finally, in 1898, the New Territories were added under a 99-year lease.  Although Hong Kong Island and Kowloon were ceded to Britain in perpetuity, the New Territories – which comprised over 90 per cent of Hong Kong's land – had such a vital role in the economy that the British government agreed to transfer sovereignty of the entirety of Hong Kong to China upon the expiration of the lease in 1997.  The transfer has been credited by some as marking the end of the British Empire.

Democratic development in Hong Kong: Democratic development in Hong Kong has been a major topic since the transfer of sovereignty to China in 1997.  The one country, two systems principle allows the Hong Kong government to administer all areas of government except foreign relations and (military) defence separately from the national Chinese government.  Many Hong Kong citizens became concerned about democratic development when the first Chief executive of Hong Kong Tung Chee-hwa appeared to have mishandled this issue.  Other democracy-related issues involving human rights and universal suffrage became the new focal point for the pro-democracy camp.  Ever since the 1950s, the Chinese government has continually threatened the British in attempting to bring any democratic developments in Hong Kong.  Attempts to bring Hong Kong citizens on to the negotiating table by the British during the Sino-Anglo discussions were rejected by Beijing in the late 1980s.  The last governor Chris Patten faced a great deal of opposition in changing the former colony's political system.

1994 Hong Kong electoral reform: The 1994 Hong Kong electoral reform was a set of significant constitutional changes in the last years of British colonial rule in Hong Kong before the handover of its sovereignty to the People's Republic of China on 1 July 1997.  The reform proposal was carried out by the last governor Chris Patten to largely broaden the electorate base of the last three-tiers elections in 1994 and 1995:

Immigration Department (Hong Kong): The Immigration Department (, known as 人民入境事務處 before the 1997 transfer of sovereignty) of the Government of Hong Kong is responsible for immigration control of Hong Kong.  After the People's Republic of China assumed sovereignty of the territory in July 1997, Hong Kong's immigration system remained largely unchanged from its British predecessor model.  Residents from mainland China do not have the right of abode in Hong Kong, nor can they enter the territory freely, both before and after 1997.  There are different regulations that apply to residents of Macau, another Special Administrative Region of China.  In addition, visa-free entry acceptance regulations into Hong Kong for passport holders of some 170 countries remain unchanged before and after 1997.

Right of abode in Hong Kong: The right of abode in Hong Kong is the right to legally reside in Hong Kong without any limit or condition of stay being imposed by the Hong Kong Immigration Department.  As the People's Republic of China stood to resume sovereignty over Hong Kong from the United Kingdom, the nationality of Hong Kong people as well as their right of abode in the territory was formalised prior to the 1997 handover.  Since Hong Kong has never been an independent country, there is no provision for its own citizenship status.  Hong Kong Permanent Resident is the legal status for those who have the right of abode in Hong Kong, which is the "de-facto" citizenship status in Hong Kong.  Most citizen rights in Hong Kong (such as the right to vote) are granted to all permanent residents, while some (such as the right to hold a HKSAR passport, or becoming a high-rank public officer such as the Chief Executive) are restricted to permanent residents who are also Chinese citizens.

Supporting paragraphs: 1994 Hong Kong electoral reform Transfer of sovereignty over Hong Kong
Answer: 1 July 1997.