these were replaced with four 9.2 in guns. The new ships, though based on the general type that had formed the basis of the preceding four battleship designs, marked the first significant change in the series. Like all late pre-dreadnoughts that entered service in the mid-1900s, Commonwealth was made almost instantaneously obsolescent by the commissioning of the all-big-gun in December 1906, armed with a battery of ten heavy guns compared to the typical four of most pre-dreadnoughts.

Commonwealth was 453 ft 9 in long overall,