The Protector at Port Adelaide.

Before the federation of Australia in 1901, each colony was responsible for the defence of its coasts and harbours. The South Australian Government financed building the Protector for this purpose, and she arrived at Port Adelaide from England on 30 September 1884.

In June 1900 during the Boxer Uprising in China, Britain made an appeal to the colonies for reinforcements to help break a siege of European communities. The Protector was part of the Colonial Naval Forces raised to assist, sailing from Port Adelaide in August with a contingent of 300 Australian volunteers (mainly from New South Wales and Victoria), who were to serve under British officers. However, the Australian contingent arrived in China too late to take part in any significant action.

On returning to Australia, the Protector participated in the ceremonies inaugurating the Australian Commonwealth on 1 January 1901. In March 1901 all naval forces of the Australian states were transferred to the Commonwealth defence service.