Diane Susan Leather Charles, née Leather, (7 January 1933 – 5 September 2018) was an English athlete who was the first woman to run a sub-5-minute mile.
Inspired to take up running aged 19 after watching the 1952 Olympic Games, within months Leather had become national cross-country champion, a title she would go on to win four times.
On the track, she first came to prominence as part of a team that broke the world record for the 3 x 880 yd (800 m) relay. Then on only her second attempt at running the mile, she broke the world record. The following year, having lost the record to Romanian athlete Edith Treybal, she reclaimed the record in a time of 5:00.2, then in the same week lowered it to 4:59.6, the first woman ever to break five minutes.