First known as New South Britain, the islands were annexed for the British Crown in the name of King George III in 1819. In 1820 the name changed to New South Shetland Island whereupon they were given their present name. In 1821 a Russian expedition lead by T.T. Bellingshausen sailed from west to east through the Bransfield Strait. Unaware that the British had discovered the islands they gave King George Island the name Waterloo; this is still used by the Russians today. The name Admiralty Bay, given by a British sealer named George Powell, appeared onmaps in 1822.

After the complete eradication of Fur seals in the South Shetlands at the end of the 19th Century, modern whaling vessels, requiring large deep bays, were developed. Admiralty Bay was found to be an ideal site for such ships. At the turn of century the industry expanded rapidly. Testimony to the near-shore nature of the early whaling industry are the whale bones found on the shores of Admiralty Bay.

It appears that the first people to winter on the island did so involuntarily. This was a group of several sealers. Also noted is a stay by 6 men who were separated from their ship the "DISCOVERY".

Up to the start of World War II there were no permanent bases in Admiralty Bay. There was a dramatic change a British military group set up base on MacKellar Peninsula in 1946/47. Later, in the same season, the Argentineans built a small hut which was used periodically. It was located only 25 meters from the British base. Five people wintered at the British station in 1948, of whom Eric Platt, base leader and Geologist, died during field studies (2). The British base was manned until its closure in 1961.