 He was the third child of six and second son of Anglican missionary Reverend Thomas Bridges (1842–98) and "the third white native of Ushuaia" (his elder brother, born in 1872, having been the first) in Tierra del Fuego, Argentina, at the southernmost tip of South America.He wrote "The Uttermost Part of the Earth" (1948) about his family's experiences in Tierra del Fuego, but it was particularly about the Yahgan and Selk'nam indigenous peoples and the effects on them of colonization by Europeans.Stephen Lucas Bridges, also called Esteban and going by Lucas, was born to Thomas and Mary Ann Bridges in Ushuaia, Tierra del Fuego.