Royal Navy Naval Blockade of Nazi Germany coast, occupied European shores and Axis members during entire war

I also would like to draw attention to British naval blockade on entire German occupied Europe shores and actual Reich itself since initiated in September 1939 and its effects to shape Axis strategic priorties. Ever since the beginning of war first with North Sea Patrol then actually hunting down all remaining German merchant ships and blockade runners in High Seas British and (Commonwealth ) Royal Navy actually put up a very effective conbtraband control and check system that prevented any kind of strategic war material supply reaching into Germans from overseas. Between 1939 and December 1940 , a total of 282 German merchant and cargo ships (more than 420.000 tons) trapped on overseas and high seas unable to return Germany after decleration of war , were hunted down by British naval patrols from Atlantic to Pacific and Indian Ocean. Most of these German vessels either scuttled themselves when cornered by Royal Navy though 80 of them were captured by the British and added to Allied war effort. Remaining German merchant marine was trapped either in their ports or in Baltic Sea (a few of them were in Mediterranean , assisted Italian war effort of supplying Africa till they were sunk) As a result Germany was cut off some vital critical war material from overseas that led premature moves like invasion of Norway and Denmark in 1940 due to threat to supply route of Swedish iron ore. Especially on oil (which Germany was heavily dependent to overseas resources ) , grain , strategic minerals like cobalt , mangnesium , copper etc and other vital materials like rubber , wool , after British declared war in September 1939 and Royal Navy put up a very effective blockade system in North Sea that extended to German coast then all occupied Europe Nazi Germany and its economy and war effort had been almost totally dependent on Soviet Union thanks to Nazi-Soviet Pact and Trade Deal signed along with in August 1939 and further trade agreements signed between Germany and Soviet Union in 1940. This first led Nazi leaders first to loot Europe wholesale and exploit it very profitable terms for them (but also very inefficiently for German war economy) especially after 1942 when German leaders declared total war but eventually it also convinced Hitler to attack , invade and destroy Soviet Union and take its entire national resource supply to make Thirds Reich self sufficient in every aspect at the expemnse of Russians and East Europeans sooner than later after 1940.

Role of Royal Navy naval blockade on Germany and Fascist Italy during WW2 is usually ignored by historians because its expected possible sudden effects of depriving Germany food and necessary resoueces (like German economy stopping and leading to a revolution in November 1918 to topple existing war regime) were neutrilised by Nazi-Soviet Trade Agreement that provided these food , oil and other strategic minerals/materials till June 1941 the very same oil , food and strategic material supplies Royal Navy blockade denied. (After invasion of course until 1944 when Germans were totally driven from Ukranie , Germans took over most of these materials in USSR ) But also this very dependency to Soviet Union Hitler and Nazi leadership passionmately hated , that led Hitler to prepare in 1940 then to start invasion of Soviet Union and start his long desired crusade against communism as soon as possible , even prematurely in 1941.

So both in Napoleonic Wars , World War I and World War II , Royal Navy used blockade weapon very efficiently tıo derail strategy of their opponents.