I've found references to three people of that name or similar. Since one of the questions was asking what army he was a General in, I'm inclined to believe that the person in question is John Gowans, who was not a general in any military force, but held the position of General of the Salvation Army 1999 - 2002. He did, however, serve in the British Army for two years - not long enough to achieve any General rank.
I see mention of a John Curtis Gowan, whose biography shows no military service. The closest thing he has is that he taught at Culver Military Academy.
There's also a John Hunter Gowan II, who was a loyalist in Ireland and was appointed head of a yeomanry corps (it has a law enforcement role), but no indication of military service in his biography.
John Curtis Gowan was born on May 21, 1912.
John Curtis Gowan was born on May 21, 1912.
John Hunter Gowan II was born in 1727.
John Hunter Gowan II died in 1824.
John Curtis Gowan died on December 2, 1986 at the age of 74.
John Curtis Gowan died on December 2, 1986 at the age of 74.
John Curtis Gowan was born on May 21, 1912 and died on December 2, 1986. John Curtis Gowan would have been 74 years old at the time of death or 103 years old today.
Gowan's birth name is Lawrence Gowan.
Matthew Gowan's birth name is Matthew Kyle Gowan.
Kurt Gowan is 6'.
Joshua Gowan is 6' 2".
David Gowan died in 1926.