Operation Retribution ( ) , also known as Operation Punishment , was the April 1941 German bombing Attack of Belgrade , the capital of the Kingdom of Yugoslavia , in retaliation for the coup d'état that overthrew Change_of_leadership the government that had signed Sign_agreement the Tripartite Pact .

It marked Recording the 50th anniversary Social_event of the Molotov–Ribbentrop Pact between the Soviet Union and Nazi Germany .

The German invasion began Process_start on 1 September 1939 , one week after the signing Sign_agreement of the Molotov–Ribbentrop Pact between Germany and the Soviet Union .

On 17 September , the Soviet Red Army invaded Attack Eastern Poland , the territory beyond the so-called Curzon Line that fell into the Soviet `` sphere of influence '' according to the secret protocol of the Molotov–Ribbentrop Pact ; this rendered Supply the Polish plan of defence Defending obsolete .

A new government formally disbanded the ÁVH , declared Expressing_publicly its intention to withdraw Escaping from the Warsaw Pact and pledged Commitment to re-establish free elections Change_of_leadership .

The Warsaw Pact invasion of Czechoslovakia , officially known as Operation Danube , was a joint Collaboration invasion of Czechoslovakia by five Warsaw Pact countries – the Soviet Union , Poland , Bulgaria , East Germany and Hungary – on the night of 20–21 August 1968 .

The Warsaw Pact invasion of Czechoslovakia , officially known as Operation Danube , was a joint Collaboration invasion of Czechoslovakia by five Warsaw Pact countries – the Soviet Union , Poland , Bulgaria , East Germany and Hungary – on the night of 20–21 August 1968 .

The Soviet ( as well as German ) invasion Attack of Poland was indirectly indicated Statement in the `` secret additional protocol '' of the Molotov–Ribbentrop Pact signed on Sign_agreement 23 August 1939 , which approximately divided Poland into `` spheres of influence '' of the two powers and questioned the future existence Presence of the Polish state .

An agreement at the Yalta Conference permitted Agree_or_refuse_to_act the Soviet Union to annex almost all of their Molotov–Ribbentrop Pact portion of the Second Polish Republic , compensating Supply the Polish People 's Republic with the greater southern part of East Prussia and territories east of the Oder–Neisse line .

That year , the revolutionaries and the Spanish signed Writing the Pact of Biak-na-Bato , which temporarily reduced hostilities .

This conflict was also the first in which New Zealand did not fight Hostile_encounter alongside the United Kingdom , instead following the loyalties of the ANZUS Pact .

It was also the last removal of a Marxist-Leninist government in a Warsaw Pact country during the events of 1989 , and the only one that violently overthrew Change_of_leadership a country 's government and executed its leader .

Two days prior to its ousting , the Cvetković government had signed Sign_agreement the Vienna Protocol on the Accession of Yugoslavia to the Tripartite Pact ( Axis ) .

The coup had been planned Arranging for several months , but the signing of the Tripartite Pact spurred the organisers to carry Imposing_obligation it out , encouraged Influence by the British Special Operations Executive .

Many sources conclude Coming_to_believe that the Soviet Union had intended to conquer all of Finland , and use Using the establishment of the puppet Finnish Communist government and the Molotov–Ribbentrop Pact 's secret protocols as evidence of this , while other sources argue Agree_or_refuse_to_act against the idea of the full Soviet conquest .