A popular figure on Edinburgh's rugby scene, Mr Southall was a "gentle giant" who was perhaps best known for his work for the Hearts and Balls charity.
Lismore teammates and his many friends joined his family this week for his funeral service at a
packed Warriston Crematorium.
Among the people to pay tribute to the father-of-two was former British Lions captain, Finlay Calder.
He said: "I'll always remember how at one game at Murrayfield, in the pouring rain, he was there in his distinctive woollen hat with a saltire on it, collecting for the Hearts and Balls charity. I think he collected something like £2000 for the charity that day."
Mr Southall, who worked for Virgin Leisure, had been with the Pleasance-based rugby club for more than 20 years. The former Trinity Academy pupil first began playing for Lismore's Second XV in the second row, whilst working at what used to be the electrical engineering firm, Ferranti, at Crewe Toll.
He became involved with Hearts and Balls in 1999 after knowing players who were left disabled by injuries on the pitch. Based in Musselburgh, the charity helps ex-players and their families to have a better quality of life.
Friend, teammate and Hearts and Balls director John Evans said Mr Southall was devoted to his wife, Pat, and children Linsday, 19, and Graham, 15.
He said: "At 6ft 4ins tall and bearded, he was something of a giant on the pitch, but away from it he was a gentle giant. I'm glad we played on the same side so I never had to face him, though.
"But first and foremost Callum was a family man.
"Callum was not the kind of person who sought the limelight at the clubhouse. He could be quiet but being someone with a liking for Monty Python was known for his ready wit and banter. Callum could bring a smile to even the most dour of people because he had that rare gift of being able to get on with everyone who met him.
"I'll remember Callum as a tall, grey ex-hippy who liked all sorts of music from Led Zeppelin and Status Quo to even the Breton pipes. He loved things with petrol engines, especially bikes, and loved to travel."
Mr Evans added: "Callum will be missed by everyone who knew him in the rugby community with his time with Lismore and his tireless dedication to raise awareness of Hearts and Balls. He was a good friend."
Mr Southall, who was also a keen hill walker and cyclist, died from a sudden heart attack at his home in Prospect Bank Gardens, Meadowbank, on April 16.
The full article contains 479 words and appears in Edinburgh Evening News newspaper.
