Entering service in 1961, Dido was involved in the Indonesia–Malaysia confrontation, served with NATO's Standing Naval Force Atlantic on several occasions, and was one of the frigates used for the filming of the drama series Warship.

Following a defence review at the start of the 1980s, the ship was transferred to the Royal New Zealand Navy (RNZN), and was recommissioned as HMNZS Southland.

She was laid down as a Rothesay-class frigate to be called Hastings on 2 December 1959, but in 1960, it was decided to complete the ship as one of the new Leander class, with the new name Dido.

Two oil-fired boilers fed steam at 550 pounds per square inch (3,800 kPa) and 850 °F (454 °C) to a pair of double reduction geared steam turbines that in turn drove two propeller shafts, with the machinery rated at 30,000 shaft horsepower (22,000 kW), giving a speed of 28 knots (52 km/h; 32 mph).

Dido was extensively refitted at Devonport between July 1975 and October 1978, as a Batch 1B Ikara conversion (and the last to be completed),[9] at a cost of £23,000,000.

It is seen as a dubious purchase, in retrospect, and by some at the time,[13] as an ageing, if recently refitted, 'over specialised anti submarine frigate'[14] without any real surface armament or surveillance radar.

As UK experience and UK Treasury costing already indicated that the 13-year-old Bacchante was too old for cost-containable structural modernisation, a view also held by the former captain of HMNZS Waikato,[17] Southland received a five-month, $15 million refit at Vosper Thornycroft after recommissioning on 18 July 1983 as HMNZS Southland.

The refit was completed in late December 1983 and over the following months, Southland had several workups at Portland and participated in a number of Royal Navy and NATO exercises before sailing for New Zealand in mid-1984.

Around 1986 extensive plans were drawn up for a major refit of Southland which would have allowed its Ikara capability to remain operational until the mid-1990s.

However quotes for refitting Southland in UK yards or at Lyttleton proved high, the Cold War effectively ended in 1989 and with the RN and USN withdrawing its stock of nuclear depth charges, (the intended warhead option for RN Ikara Leanders to attack Soviet submarines at 10–20 kilometres (5.4–10.8 nmi) range, where two directional sound transmission times were probably too great for accurate proximity direction of Ikara carrying MK 46 torpedoes) meant Ikara was no longer useful to the Royal Navy.