Answer: 8
8 teams would win the Highland League between the two wars:
Buckie Thistle 5 - 1919/20, 1926/27, 1927/28, 1933/34, 1936/37
Clachnacuddin 5 - 1920/21, 1921/22, 1922/23, 1923/24, 1938/39
Caledonian 2 - 1925/26, 1930/31
Inverness Thistle 2 - 1928/29, 1935/36
Elgin City 2 - 1931/32, 1934/35
Fraserburgh 2 - 1932/33, 1937/38
Huntly 1 - 1929/30
Aberdeen 'A' 1 - 1924/25
The period between the World Wars also saw the Highland League grow in numbers, from an average of 8 pre-war to an average of between 12 to 14 teams taking part.