The significant military strategy employed during World War II was Blitzkrieg, or "lightning war." This tactic emphasized rapid, coordinated assaults combining air attacks, artillery bombardments, and swift ground troop movements to overwhelm and incapacitate the enemy quickly. Debuting during the invasion of Poland in 1939, Blitzkrieg sought to avoid the stalemate associated with trench warfare by using speed and audacity to achieve swift victories. The effectiveness of this strategy enabled Germany to overrun much of Europe before facing resistance. Blitzkrieg's principles also influenced modern military tactics and demonstrated the changing nature of warfare in the 20th century.