Overseal, Derbyshire born centre half Ernie Hart began playing local junior football with Overseal Juniors in 1918 and Doncaster & District Junior League club Woodland Wesleyans in 1919, joining Leeds United in September 1920. He made his Leeds United debut in an FA Cup tie against non league Boothtown in September 1920 and his Football League debut against Stockport County the following February. By 1922-23 he was fully established in the team, missing only one match that season. He played 16 seasons at Leeds United, being part of the 1924 team that won the Second Division Championship and being twice promoted as runners up in the Second Division in 1928 and 1932 after subsequent relegations (he missed most of the 1926-27 season with injury and without him they went down).
In November 1928 he received his first of 8 England caps against Wales at Swansea, including an appearance in the England team that beat Austria 4-3 in 1932 – the Austria side of the early 1930’s were regarded as Continental Europe’s strongest side, and had gone 14 matches unbeaten when they met England. His final cap was in a 2-1 defeat to Czechoslovakia in Prague in May 1934. His international career should have been longer, but he lost his England place as a result of a ban imposed for swearing at a referee. He also toured South Africa with the Football Association in the summer of 1929 and that October played for The Professionals in the 1929 FA Charity Shield, a match they won 3-0 against The Amateurs. He also made three appearances for The Football League.
He continued playing for Leeds until April 1936 when, after 15 goals in 472 games he had a single season at Mansfield Town before retirement, joining them for £350 in August 1936, playing 30 times for The Stags. After a spell scouting for Coventry City he then became player manager at Tunbridge Wells Rangers in July 1938 where he stayed until the club folded early in the Second World War in January 1940.