The 26th Amendment to the United States Constitution lowered the voting age from 21 to 18 years old. It was ratified on July 1, 1971, making it the fastest ratification of any amendment in U.S. history.
The reasoning behind finally ratifying the 26th Amendment in 1971 was largely due to the political climate of the time. The amendment was proposed in the aftermath of the Vietnam War when many young Americans who were eligible to be drafted and fight in the war were not yet old enough to vote. This created a sense of injustice and led to widespread protests and activism by young people who demanded the right to have a say in the decisions that affected their lives.