World War II started when Germany invaded which country? Answer
World War II officially started right after Germany start invading Poland.
The invasion of Poland began on September 1, 1939, when German forces, using their swift military doctrine known as Blitzkrieg (“lightning war”), crossed the border. This act of aggression violated international agreements and triggered the declarations of war that formally commenced the global conflict. The attack utilized rapid movements of motorized infantry and tanks, fully supported by the air force, designed to quickly overwhelm Polish defenses.
Following this invasion, Great Britain and France, who had guaranteed Poland’s security, issued an ultimatum to Germany demanding an immediate withdrawal. When Germany refused to comply, both nations declared war on Germany on September 3, 1939, officially plunging Europe and the world into the largest conflict in human history.
Source:
https://www.youtube.com/watch?v=Cj1sXT5wY0Q
https://www.threads.com/@beliproduk.official/post/DSBdFOckmFb