From the start of the war the Royal Navy had to shoulder the burden of fending off the U-boats.
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Already during the summer of 1941 the USN was escorting convoys and attacking U-boats. These pages include the Coast Guard.
The RCN provided a critial part of the convoy system. Its victories and losses are covered here.
The RAN took place in the distant Battle of the Atlantic, sinking one U-boat.
Cooperation between Allied Navies
So, how did the partnership work out?
Destroyer escorts, Sloops,
Corvettes and all the other vessels charged with defending the convoys and the sea lanes.
Escort Carrier development
The story of USS Bogue
The story of USS Guadalcanal
Polish naval forces
Dutch naval forces
Greek naval forces
Soviet Naval forces
Norwegian naval forces
Free French Navy
South African Navy