Bartolomeo Colleoni was an Italian Giussano-class light cruiser, that served in the Regia Marina (Royal Navy) during World War II.

In the aftermath of World War I, the Italian Regia Marina (Royal Navy) received a group of light cruisers from the defeated German and Austro-Hungarian fleets.

At the time, the Italian naval command was satisfied with these vessels as a supplement to their existing scout cruisers in the immediate postwar era.

After the French Navy began building twelve large destroyers of the Chacal and Guépard classes, the Italian command responded by ordering the four Giussano-class cruisers.

[5] The ship's armor belt was 24 mm (0.94 in) thick, extending only for the length of the hull that contained the propulsion machinery spaces and the ammunition magazines.

Bartolomeo Colleoni departed Italy on 5 September and arrived in Barcelona on 3 October, where she protected Italian nationals in the area.

The ship cruised in Chinese waters for nearly a year, until October 1939, when she was recalled home in response to the start of World War II in September.

[7] On 7 July, Bartolomeo Colleoni and Giovanni delle Bande Nere sortied as part of the escort for a large convoy sailing to Benghazi in Libya.

[9] The convoy consisted of five freighters and a passenger liner that were carrying some 2,200 men, 72 tanks, 237 other vehicles, and a large amount of supplies and fuel; these were intended to fortify the planned invasion of Egypt.

II Division, along with the 10th Destroyer Squadron (which consisted of Maestrale, Libeccio, Grecale, and Scirocco) and the torpedo boats Pegaso, Orione, Orsa, Procione, Abba, and Pilo, formed the convoy's close escort.

In the ensuing Battle of Calabria on 9 July, the ships of II Division were assigned to make sure the convoy arrived in port undamaged.

The convoy arrived in Benghazi the next day, but Bartolomeo Colleoni and Giovanni delle Bande Nere soon moved to Tripoli to avoid attacks from British aircraft based in Egypt.

The Italian naval command considered sending the two cruisers to bombard British positions on the coast at Sollum, but decided against it; instead, they were to be sent to Portolago in the Dodecanese.

[9] Bartolomeo Colleoni and Giovanni delle Bande Nere left Tripoli on the evening of 17 July and sailed to the north of Crete, bound for the Aegean.

At around 06:00 on 19 July, the Italians spotted the four British destroyers off Cape Spada of western Crete, which were some 17,000 m (19,000 yd) away; Sydney and Havock were around 60 nautical miles (110 km; 69 mi) to the north.

The Australian cruiser had opened fire from a range of about 12,000 m (13,000 yd) while in the middle of a fog bank; almost immediately, she hit Giovanni delle Bande Nere near her aft funnel.

The Italian cruisers quickly returned fire, but had difficulty locating the target in the fog, as they only had Sydney's muzzle flashes to aim at.

[14] At 08:24, Sydney struck Bartolomeo Colleoni with a salvo of 152 mm shells; one of the rounds jammed her rudder in the neutral position.

Sydney, Hero, and Hasty continued the pursuit of Giovanni delle Bande Nere, but Ilex, Havock, and Hyperion approached the area that survivors from Bartolomeo Colleoni were floating.

They also point out that Italian gunnery was less accurate than their British counterparts, which compounded Casardi's decision to fight at long range.