Timeline 

1942 – Born in Uphall, Scotland, on 17th December to parents Anne and William MacCallum
1960s – Serves in the RAF (Royal Air Force)
1969 – Begins training Taekwon-Do in Singapore
1971 – Promoted to 1st Dan (S-130) in the presence of General Choi Hong Hi on 4th July
1972 – Leaves RAF and returns to Scotland
1973 – Founded Bathgate Taekwon-Do club
1975 – Promoted to 2nd Dan (B-2-13) on 7th March
1977 – Founded Grangemouth Taekwon-Do club. Promoted to 3rd Dan (B-3-11) on 4th September
1978 – Founded Livingston Taekwon-Do club
1975 – Becomes Secretary General of the UKTA (United Kingdom Taekwon-Do Association), holds position until 1985
1976 – Winner National Power Gold for Twimyo Dollyo Chagi 
1977 – Becomes a fulltime Taekwon-Do instructor
1979 – Becomes Secretary General of the AETF (All Europe Taekwon-Do Association), holds position until 1985
1980 – Promoted to 4th Dan (B80-4-6) on 22nd March. Also became an International Instructor (Cert. no. 252) and International Umpire 'A' (Cert. no. 188) on this day
1982 – Married Morag MacCallum (née Sutherland), author of HGM MacCallum's memoirs
1984 – Promoted to 5th Dan (B84-5-2) on 22nd July
1985 – Moves to Vienna and becomes Under Secretary General of the ITF, holds position until 2002
1988 – Promoted to 6th Dan (GB-6-1) on 1st September
1994 – Promoted to 7th Dan Master (ITF-7-1) on 22nd July
2001 – Promoted to 8th Dan (ITF-8-1) on 2nd March
2002 – Becomes Secretary General of the ITF, holds position until 2007
2007 – Becomes Treasurer  of the ITF, holds position until 2015
2009 – Promoted to 9th Dan Grand Master (GB-9-1) on 21st March
2012 – Becomes President of ITF Scotland, holds position until 2016
2015 – Becomes Board Member of the ITF, holds position until 2019
2015 – Induction into the ITF Hall of Fame, for his contribution in the development of the ITF
2019 – Officially named an Icon of the ITF
2019 – Bestowed the title of First Honourable Grand Master (Kwan Jang Nim) in the ITF
2020s – Chair of the ITF's Grand Master Promotion Committee
2023 – Completion of Number Nine's first draft
2024 – Death of Morag MacCallum, Number Nine's author and HGM MacCallum's wife, on 4th February
2025 – Death of HGM MacCallum on 30th January

Travelled globally with General Choi from the 1980's until 2002, also as Gen. Choi's bodyguard and took part in Gen. Choi's last IIC in Denver, Colorado, in April 2002.