The idea of a military draft goes back a long way in world history -- countries have conscripted men to fight their wars since antiquity. Conscription didn’t come naturally to Americans, who had been suspicious of overbearing government power since colonial days, and it wasn’t until the two major wars of the 20th century that the military draft began to play a part in the life of young American males.

Raising Armies

As the Revolutionary War began, much of the fighting on the colonial side was done by state militias. The Continental Army was raised by offering prospective soldiers bonuses -- both cash and an offer of free land after the war's end -- to enlist. But militias were poorly trained and armed, while regular army soldiers enlisting for hope of financial reward did not always prove to be the best fighters. After he became president, George Washington attempted to register all American men for service, but this was not a popular measure, and it failed to pass Congress.

Draft Riots

The Civil War saw the first major draft in American history, when Congress gave President Abraham Lincoln the power to force all men between the ages of 20 and 45 to register for military duty. This was a highly unpopular measure, in part because of the inequity of the law, since it allowed those who could afford to do so to hire a substitute to perform their military service for them. The worst draft riots in American history took place in New York City in 1863, when 1,000 people died and Union troops were called to put down the riots.

First Draft Laws Passed

On the eve of America’s entry into World War I in 1917, Congress passed the Selective Service Act. As in the Civil War, this was an unpopular measure, with hundreds of thousands of men failing to register, but eventually more than 2.8 million men were inducted into military service for World War I. The Selective Service and Training Act of 1940 was the first peacetime draft in America’s history. After it was signed into law by President Franklin Roosevelt, the military would induct more than 10 million men to serve in all theaters of World War II.

An All-Volunteer Force

The Vietnam War saw more than 1.8 million men drafted. But the most serious draft protests since the Civil War called the fairness of the draft into question, mainly because student deferments gave wealthier young men a way to avoid service. To remedy this, a lottery was put into effect in 1969, which chose men for service based on random drawings of birth dates. The draft ended in 1973, and since then the United States has maintained all-volunteer armed forces, although male citizens between the ages of 18 and 25 are still required to register with the Selective Service System. While women can volunteer to join the armed forces, the law does not require them to register with Selective Service.