Confederate States of America
Having a smaller navy than its northern neighbour the Confederate States Navy doctrine was to sacrifice armour for speed and in general the CSN ships were 3-5 knots faster. Collaboration with their Northern neighbours never really took untill the Japanese attacks on Hawaii and the Phillipines drew the two Americas into the war at the same time. While they were then allies. The cooperation was in having one headquarters command structure but the fleets and armies remained separate entities though they may have fought together in the same battles. The CSA Task Forces were just as active in both the Pacific and Atlantic theaters. The main cooperation along with the UK/Commonwealth was in the realms of RADAR, SONAR/ASDIC and other fire support apparatus. The CSA's Treaty with France meant that when the French surrendered in 1940 the surviving Fleet units went and interned themselves at CSA ports till the CSA entered the war at which stage the French units received needed refits and rejoined the Allies. The French had been in cooperation with the CSN during the 1920's and 30's which enabled the CSN to be the only other navy to field the auto 5.1" twin and quad turrets of French design.
Biscayne Bay, Florida during the 1930's.