McGrory is also the all-time leading goalscorer in top-flight British football, with a total of 550 goals in 547 competitive first-team games at club and international level.

Henry and Catherine had been married at Saint Baithin's Church (known locally as 'the Chapel') in St Johnston, a village in The Laggan district in the east of County Donegal, before emigrating to Scotland.

[12] The 1924–25 season started poorly, with McGrory not scoring in his first three games, but worse was to come when his father was killed after accidentally being struck by a stone in a local park.

McGrory played against Falkirk the following Saturday, just hours after having just attended his father's funeral, and yet managed to get off the mark for the season with his first goal in a 2–1 win.

[13] McGrory returned in stunning form in the Scottish Cup, scoring a hat-trick against Third Lanark and a double against Rangers in a 5–0 semi-final victory.

He then headed a last minute winning goal in the 2–1 Scottish Cup Final victory over Dundee on 11 April 1925, the first major honour of his career.

[17] Celtic reached their second successive Scottish Cup Final, but McGrory this time was on the losing side as they lost 2–0 to St Mirren.

[18] He was just as prolific in the 1926–27 Scottish Cup, where he scored nine goals in only six outings,[19] although in a cruel twist of fate he missed out on playing in the final, which Celtic won against East Fife 3–1, due to breaking two ribs in an April league defeat to Falkirk.

[20] Despite missing the final, he still received a winner's medal on manager Willie Maley's recommendation due to the goals he had scored during their cup run.

[19][22] By the late 1920s McGrory was a wanted man; in five seasons he had scored 143 League and Scottish Cup goals in just 152 games, and Celtic had already received and turned down countless offers for him.

What McGrory didn't know was that Celtic had arranged a meeting with Arsenal manager Herbert Chapman and chairman Sir Samuel Hill-Wood MP in London.

[23] In the aftermath of his refusal to leave Celtic, McGrory's weekly wage was reduced from £9 to £8 from the beginning of the season, with no warning or reason given.

McGrory spent a lengthy spell on the sidelines after picking up a very bad injury in an appearance for the Scottish League XI at Villa Park in November 1928.

In the Cup Final on 11 April 1931, he scored the opening goal in a 2–2 draw against Motherwell in front of crowd of 104,863 at Hampden Park, Glasgow.

[34] A huge factor in Celtic's indifferent season was the death of their goalkeeper John Thomson on 5 September 1931 at Ibrox Park.

Rangers forward Sam English collided with Thomson and his knee struck the Celtic goalkeepers temple, fracturing his skull.

[35] McGrory, on top of losing a teammate and friend, was succumbing to more serious injuries and missed large chunks of the season,[36] only playing in 22 of the 38 League games.

[30] On 14 March 1936, McGrory achieved the fastest hat-trick in Scottish League history, scoring three goals in less than 3 minutes, during a 5–0 win over Motherwell.

[2] Kilmarnock were struggling in the league, and lost their first two games under McGrory; a humiliating 9–1 rout at the hands of Celtic in his debut as manager and a 4–0 loss to Hibernian.

[52] Hopes that McGrory's side of efficient journeymen and enthusiastic youngsters could progress further were quashed by Britain's declaration of war against Germany in September 1939.

[59] Winger Jimmy Delaney's sale to Manchester United in February 1946, after asking Celtic for a £2 rise in his weekly wage, and the transfer of Malky MacDonald to Kilmarnock further weakened the side.

[64] A further defeat against Third Lanark in September 1946 saw a large number of fans protest outside the ground, although it was the chairman Tom White who was subject of their criticism and not McGrory.

[61] For the next 18 years, Kelly would be the dominant personality at Celtic Park; imposing his will in the running of the club at all levels including having direct involvement in team selection.

[70] Tully was a charismatic performer who combined audacious dribbling with outright showboating and razor sharp wit, making him hugely popular with the Celtic support.

In April 1951, a John McPhail goal saw Celtic defeat Motherwell 1–0 in the Scottish Cup Final for the club's first major trophy since the war.

[81] His time as manager, however, is considered largely a period of underachievement, and with chairman Robert Kelly's domineering influence in the running of the club, many questioned how much say McGrory had in team selection.

Drawn against Spanish side Valencia in the first round, Celtic were beaten 4–2 in the first leg in Spain on 24 October 1962,[86] having trailed 3–0 at half time.

Celtic belied their mediocre domestic form in Scotland by reaching the semi-final of the tournament, eliminating Basel, Dinamo Zagreb and Slovan Bratislava en route.

[89] A combination of tactical naïveté and questionable refereeing saw Celtic slump to a 4–0 defeat in the return leg in Hungary and go out on aggregate.

[91] At this time, the Celtic board appointed McGrory to the new role of Public Relations Officer,[91] a post he would retain until his retirement in 1979.