Sheffield born wing half Len Ermitage played for Wadsley Bridge in 1914 but after the First World War joined First Division Sheffield Wednesday in August 1919, making his Football League debut at Notts County that September, but only playing 3 matches in a season which saw Wednesday relegated. He joined Leeds United in June 1920 scoring on his debut against South Shields that September and enjoying three seasons at Elland Road which saw him score 14 times in 53 appearances, before he joined Wigan Borough in May 1923. A single season at Springfield Park brought goals a plenty, he was the club’s top scorer with 22 goals in 31 games during 1923-24, which brought him to the attention of Stoke who signed him in March 1924 in exchange for Andy Smith and converted him into a half back. Armitage was described as “strong as a bull” and noted for his bravery and stamina.
He played three Second Division games at the end of the 1923-24 season and 18 games in 1924-25, as The Potters avoided relegation after finishing just a single point ahead of Crystal Palace. He featured 14 times in 1925-26 as the club (now called Stoke City) was relegated after tallying three points fewer than the previous season. Injuries and illness restricted him to five goals in only 22 games in 1926-27, as he helped Stoke to win the Third Division (North) title at the first attempt. He managed to make 41 appearances in the 1927-28 season, as City finished in fifth place, just five points short of the promotion places. He played 40 games in 1928-29, as Stoke this time finished seven points short of promotion.
He went on The FA Tour to South Africa in the summer of 1929 and played for The Professionals in the 1929 FA Charity Shield in a match they won 3-0 against The Amateurs at The Den. Stoke dropped to 11th in 1929-30, with Armitage playing 31 games. He featured 27 times in 1930-31, as City again finished 11th. He played four games in 1931-32, before losing his first team place to Bill Robertson and leaving the Victoria Ground after 25 goals in 202 appearances for a brief spell with Rhyl Athletic.
Armitage joined Port Vale in December 1932. He started off with a first team spot but soon lost it to the more youthful Jack Round, as Armitage struggled with a knee injury. He posted 11 appearances in 1932-33 scoring twice, but played just the one Second Division game and one FA Cup tie in 1933-34 before he left The Old Recreation Ground on a free transfer in May 1934.
His grandfather, Tom, was a cricketer who played for England in their inaugural Test match.