Muhammad Ali, widely considered one of the greatest boxers of all time, had a career that spanned over two decades. 


Many experts believe that Ali peaked as a boxer in the 1960s, specifically in the middle to late part of the decade.


In 1964, Ali, then known as Cassius Clay, won the heavyweight championship by defeating Sonny Liston. 


This was a huge upset and marked the beginning of Ali's rise to superstardom. 


He quickly established himself as one of the most dominant and exciting fighters in the sport, with a unique combination of speed, power, and showmanship.


Throughout the rest of the decade, Ali continued to defend his title and defeated some of the top fighters of his era, such as George Foreman, Joe Frazier, and Ken Norton. 


He was known for his quick footwork, his ability to "float like a butterfly and sting like a bee," and his clever trash-talking, which helped to build up the hype for his fights.


In 1967, Ali was stripped of his title for refusing to serve in the Vietnam War, but he returned to the ring in 1970 and continued to fight, winning the title for a second time in 1974.


In summary, Muhammad Ali's peak as a boxer came in the 1960s, when he won the heavyweight championship and defeated some of the top fighters of his era. 


He was known for his speed, power, showmanship, and clever trash-talking. His prime was cut short due to the Vietnam war, but he returned to the ring and regained the title. 


Ali's impact on the sport and culture is undeniable and his legacy lives on till today.