Over the course of human history, the world has seen the rise and fall of hundreds of armies. There are many factors that come into play when we look at the size of the army maintained by any individual country, most obviously the question of whether or not that country was actively engaged in warfare during the time in question.
But other elements come into play as well: the country’s total population, interest in protecting its borders or actively conquering other countries, and of course, its financial might. Armies are not cheap! What we see when we look at data spanning 1816 to 2017 is that a handful of countries have always hovered near the top, but there have been some surprise players along the way that upended the traditional order.
In terms of sheer size, Russia has almost always dominated. Beginning in 1816, it held the top spot at about 800,000 members. Over the next decade, that number dipped as low as 600,000 and rose to over 1 million. But Russia still far surpassed the next nearest armies in size, Austria-Hungary and France at between 200,000 and 300,000 active members during the first half of the 1800s.
We think of the United States as one of the world’s military super powers, but this hasn’t always been the case in terms of its numbers. Though the precursor to today’s U.S. Army was formed in 1775 in order to fight the British, America wasn’t considered a player on the world’s military stage. By 1849 there were still only 60,000 members.
In 1860, China toppled Russia and took the top spot with an army of over 1 million members, while Russia had reduced to about 750,000 members. But the U.S. was also steadily building and became the number one largest army in the world by 1865 with 1,061,242 members. That put Russia in third place.
However, the U.S. quickly shrunk its numbers to around 76,000, putting it in roughly equal territory with Brazil. China continued to hold the number one position. For many more years, Russia and China traded off the top spot, with Austria-Hungary, France, and Germany shifting around below them.
In 1878, Turkey (which had been building up its army for years) briefly rose to the number 4 position with 461,000 members. Meanwhile, by 1888, the United States ranked as the 13th largest army with only 39,000 members. Turkey again swelled in 1898 to take the 5th position with over 420,000 troops.
Into the 1900s, Russia and China continued to swap the top spot, with Russia clocking in at over 2 million members in 1905. Though it shrunk again relatively quickly to about 1.5 million, this was temporary. By the beginning of 1915, Russia had over 2.5 million members in its army. By the end of that year, it had over 10 million. This corresponds with Russia’s second and last major offensive campaign of World War I. Meanwhile, China fell all the way to fifth position with less than half a million.
Not until 1943 did America claim the top spot with nearly 9 million members; this would swell to nearly 12 million by 1945. This corresponds with America’s involvement in World War II, which began in 1939 and continued until 1945. Over the next several decades, China, Russia, and the U.S. toggled through the top three spots.
India really came on the scene in the early 1960s and held the number four position until around 1985. By the early 2000s, India actually rose to the number two slot with over 2 million members. It held on behind China for some time, but finally took the top spot in 2016, where it remained as of 2017 (the last year for which we have data).
As of 2017, the world’s top five armies were India, China, North Korea, Russia, and the United States. With such massive firepower and touchy diplomatic relations, it is more important than ever that we stay abreast of the competition between the world’s five largest armies.
The information in this article comes from the International Institute for Strategic Studies (IISS) and includes active duty personnel and paramilitary forces whose organization, training, equipment, and control position them to support or replace official military forces.