He was born in Handsworth, Birmingham on 15 January 1949, the third of six children of John and Mary Stewart. After the two eldest children (Carol and Peter) were born in Scotland, the family relocated from Musselburgh to Mary's native Birmingham in 1948.
To many particularly of a certain age in Scotland, Ian Stewart is best remembered for his magnificent victory in the 5,000 metres at the 1970 Commonwealth Games in Edinburgh. In front of his "home" crowd at Meadowbank Stadium, the 21-year-old defeated Ian McCafferty and two legendary world distance stars, Kipchoge Keino and Ron Clarke in a European record time of 13:22:8.
However, this was only one of many international successes in a remarkable athletics career.
After initially joining Small Heath Harriers, Ian moved to Birchfield Harriers where his older brother Peter was already a member.
Geoff Warr coached the brothers and Ian's initial notable successes were achieved over the country. He became Midland Youth champion in 1966 and was runner up in the Youths National Cross Country at Norwich in 1967 before becoming Midland and National champion as a first year Junior in 1968.
After reading an article about the American miler Jim Ryan, Stewart "jacked up his weekly mileage" to include a 16 miles run on Sunday mornings followed in the afternoon by ten miles fartlek in two neighbouring Perry Barr parks. The teenager's enterprise and single-mindedness soon paid dividends.
In 1969 a couple of months after his 20th birthday, the Birmingham gun tester won the first of several international titles over 3,000m at the European Indoor Championships in Belgrade in a UK Indoor record time of 7 mins 55.4 secs.
Three months later on 11 June 1969 at Reading, Ian and his older brother Peter became the first brothers in the world to break the four minutes barrier for the one-mile in a race won by fellow Scotsman, Ian McCafferty. Ian Stewart clocked 3 mins 57.3 secs, four-tenths of a second ahead of Peter.
In early August, Stewart won his first AAA outdoor title over 5,000 metres in 13:39:8.
The Stag defeated the specialist milers John Boulter and the tall marine Jim Douglas to create a British record of 3m 39.0 secs in a three a side Great Britain versus France match on 1 September at the White City.
Eighteen days later Ian displayed maturity beyond his years to complete a European double, winning the 5,000m in Athens. After finding himself in the lead early on, he stepped aside and invited the rest of the field to take their share of the work before unleashing what was to become his trademark long surge for home. He crossed the finishing line alone in 13m 44.8 secs.