It opened as a hotel in 1928, but the building was completed earlier than that. From the hotel group's website:
1927 - The Peninsula taken over by military authorities, accommodating The Second Battalion, The Coldstream Guards and a battalion of The Devonshire Regiment; soldiers vacated the hotel a year later.
1928 - The Peninsula officially opened to the public by Sir Wilfred Thomas Southorn CMG, Governor of Hong Kong. <Read more ...>