The J class was designed by the Royal Navy in response to reported German submarines with surface speeds over 18 knots (33 km/h; 21 mph).

[1] Armament consisted of six 18-inch (450 mm) torpedo tubes (four forward, one on each beam), plus a 4-inch deck gun.

[1] Originally, the gun was mounted on a breastwork fitted forward of the conning tower, but the breastwork was later extended to the bow and merged into the hull for streamlining, and the gun was relocated to a platform fitted to the front of the conning tower.

In November 1916, a German force of half a destroyer flotilla, three dreadnoughts, and a battlecruiser set out from port to rescue two submarines U-20 and U-30 that were stranded in fog off Jutland.

[4] After the war, the British Admiralty decided that the best way to protect the Pacific region was with a force of submarines and cruisers.

[1] To this end, they offered the six surviving submarines of the J class to the Royal Australian Navy as gifts.