At age seven his parents divorced and his mother took her young family to live in Tiree, Scotland where the children were educated.
When World War I broke out Kenneth enlisted at age 16 in the Army. He did not see action until age 18 when he was assigned to the 2/8th Argyll and Sutherland Highlanders until captured and tortured. He was honorably discharged.
He then joined the Merchant Navy as a radio operator and eventually became Chief Radio Operator. He changed shipping lines several times and finally was employed on the ship 'Discovery' as 1st Offcer on its first voyage of Antarctic research and exploration called the 'BANZARE' expedition (British, Australian & New Zealand Antarctic Research Expedition). Having completed this voyage the ship sailed to Melbourne Australia where Kenneth was promoted to Captain.
On the second 'BANZARE' Antartic voyage (1930-1931) the crew discovered several new areas as well as a sea that was named 'MacKenzie's Sea' (near the Amery Ice Shelf) after the Captain. The ship was then returned to London. Subsequently MacKenzie was awarded the 'Polar Medal', inscribed 'Antarctica 1929–1931', by King George V at Buckingham Palace, London.
He then became Master of the new research ship 'Mabahiss and was to conduct voyages of oceanographic research of the north western Indian Ocean between 1933-1934.