In this article, we look at the 20 largest armed forces in the world ranked by active military personnel. You can skip our detailed analysis on trends in the defense industry and head over directly to the 5 Largest Armed Forces in the World Ranked by Active Military Personnel. Russia’s invasion of Ukraine in February 2022 sent shockwaves across the world. Most of all in Europe. Countries in the region are racking up their defenses amid the turmoil in their neighborhood.