|Full name||William Armstrong Henry|
|Date of birth||6 September 1884|
|Place of birth||Glasgow, Scotland|
|Date of death||c. 1960 (aged 75–76)|
|* Senior club appearances and goals counted for the domestic league only|
Henry was born in Glasgow and began his football career in Scotland with Rangers and then Falkirk before transferring to Leicester City in England in September 1909. He played 96 times for Leicester before Manchester City purchased him for £1,000 in 1911, the highest fee that Leicester City had received for one of their players at the time. He made his Manchester City debut in a 1–1 draw against Sunderland in November 1911. He went on to make 157 appearances for Manchester City in which he scored one goal. The war hindered his outings for City but he did spend eight years there, the majority of his career. He never got a first-team cap for Scotland, but did get international honours in a military game between England and Scotland at Everton's Goodison Park ground.
- Joyce, Michael (2012). Football League Players' Records 1888 to 1939. Nottingham: Tony Brown. p. 135. ISBN 978-1905891610.
- "Billy Henry – Manchester City and the First World War". Football and the First World War. Retrieved 27 June 2018.
- "Henry Billy Image 3 Manchester City 1913 – Vintage Footballers". vintagefootballers.com. Retrieved 27 June 2018.
- "Rangers Player Willie Henry Details". www.fitbastats.com. Retrieved 27 June 2018.
- Litster, John. Record of Pre-War Scottish League Players. Norwich: PM Publications.
- "Billy Henry – Player Profile – Leicester City Stats – FoxesTalk Forum". Foxestalk.co.uk. Retrieved 30 October 2012.
- "William A Henry". www.londonhearts.com. London Hearts Supporters' Club. Retrieved 22 January 2014.