Annie Montague Alexander was born in Honolulu, then part of the Kingdom of Hawaii, to sugar-plantation magnate Samuel Thomas Alexander and Martha Eliza Cooke.
Annie Montague Alexander was born on December 29, 1867, in Honolulu, in what was then the independent Kingdom of Hawaii. She was the eldest of seven children born to Samuel Thomas Alexander, a co-founder of the Alexander & Baldwin sugar company, and his wife Martha Eliza Cooke, whose parents were missionaries to Hawaii.
Her early childhood on the Hawaiian Islands, surrounded by plantation life, missionary values, and the natural beauty of the islands, instilled in her a lifelong fascination with the natural world. The family's considerable wealth from the sugar industry would later provide Annie with the financial independence to pursue an unconventional life as a naturalist, collector, and patron of science at a time when few women had the means or social latitude to do so.
In 1882, when Annie was a teenager, the family relocated to Oakland, California, seeking better educational opportunities and establishing the base from which she would later launch her scientific expeditions. Her Hawaiian birth and the frontier spirit of plantation society are often cited by biographers as formative influences on the independence, physical toughness, and appetite for risk that characterized her later expeditions to remote parts of the American West and Africa.