HMS Princess Margaret was a minelayer operated by the British Royal Navy during and after the First World War. She was built by the Scottish shipbuilder William Denny for the Canadian Pacific Railway as a liner to serve on the Pacific West Coast, and as such was powered by geared steam turbines, giving a speed of 23 knots.

HMS Princess Irene was a 5,394 GRT ocean liner which was built in 1914 by William Denny and Brothers Ltd, Dumbarton, Scotland for the Canadian Pacific Railway. She was requisitioned by the Royal Navy on completion and converted to an auxiliary minelayer. On 27 May 1915, she exploded and sank off Sheerness, Kent, while being loaded with mines prior to a deployment mission, with the loss of 352 lives.