 Although born in Auckland, Cowan spent his childhood in Kihikihi, on the border of the King Country.The farm was on land confiscated from the Waikato Māori, and contained part of the site of the battlefield of Orakau.Settler militia were based at a military blockhouse close to his home, while there was a considerable Māori community in the area, and the young Cowan grew up speaking both English and Māori.