Bastian was born in Bremen, at the time a state of the German Confederation, into a prosperous bourgeois German family of merchants. His career at university was broad almost to the point of being eccentric. He studied law at the Ruprecht Karl University of Heidelberg, and biology at what is today Humboldt University of Berlin, the Friedrich Schiller University of Jena, and the University of Würzburg. It was at this last university that he attended lectures by Rudolf Virchow and developed an interest in what was then known as 'ethnology'. He finally settled on medicine and earned a degree from Prague in 1850.

Bastian became a ship's doctor and began an eight-year voyage that took him around the world. This was the first of what would be a quarter of a century of travels. He returned to Germany in 1859 and wrote a popular account of his travels along with an ambitious three-volume work entitled Man in History, which became one of his most well-known works.

In 1861 he undertook a four-year trip to Southeast Asia and his account of this trip, The People of East Asia ran to six volumes. when Bastian finally published the studies and observations during his Journey through Cambodia to Cochinchina in Germany in 1868 - told in detail but uninspiredly, above all without a single one of his drawings - this work hardly made an impression, while everyone was talking about Henri Mouhot's posthumous work with vivid descriptions of Angkor, Travels in the Central Parts of Indo-China, Siam, Cambodia and Laos, published in 1864 through the Royal Geographical Society.