George Augustus Selwyn was born on April 5, 1809, at Hampstead, London. He was prepared at Eton, and in 1831 was graduated from St. Johns College, Cambridge, of which he became a Fellow.

Ordained in 1833, Selwyn served as a curate at Windsor until his selection as first Bishop of New Zealand in 1841. On the voyage to his new field, he mastered the Maori language and was able to preach in it upon his arrival. In the tragic ten-year war between the English and the Maoris, Selwyn was able to minister to both sides, and to keep the affection and admiration of both natives and colonists. He began missionary work in the Pacific islands in 1847.