St Martin’s, Shropshire born right back Harry Millership started his football career with Welsh club Chirk in 1910, joining Goole Town in 1911 and playing for Fryston Colliery in 1912. In October 1912 he was signed by Second Division club Blackpool, making his Football League debut at Huddersfield Town that December. He made 30 appearances for Blackpool before peacetime football was suspended due to the onset of the First World War in May 1915, and during the War Millership guested with Leeds City and became a regular after his debut at Huddersfield Town in December of 1917. He was a member of the Leeds City team that became unofficial Champions of England after defeating Stoke in a two-legged play-off Final in May 1918. Millership played at right back in both legs, scoring 6 goals in 49 wartime appearances for The Peacocks.
After the War he joined Leeds City in August 1919 and made his debut for his new club against his old club, in a 4-2 defeat at Blackpool on 30th August 1919, playing 8 matches until the club was suspended and had to resign from The Football League. Millership was auctioned to Rotherham County for £1,000, the second highest sum paid for any member of the Leeds City playing staff, and he made his Rotherham debut in a defeat at Stoke at the end of the month. In three seasons he scored 7 goals in 83 appearances for The Millers, before joining Barnsley in September 1922. However he failed to make much impact at Oakwell playing only 5 times in the autumn of 1922 before joining Midland League club Castleford Town in July the following year, his final club before his eventual retirement.