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 (香港旗), British Hong Kong flag (英屬香港旗) or the Dragon and Lion flag (龍獅旗).[1] 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.[2] While the flag lost its official status following the 1 July 1997 transfer of sovereignty over Hong Kong, it resurfaced in the 2010s as a symbol of increased Hong Kong autonomy and protest against Communist Chinese rule in Hong Kong.
Source : Wikipedia