Alexander von Humboldt

Alexander von Humboldt was born on 14 September 1769 in Berlin, the son of a Prussian officer and chamberlain and of Marie-Elisabeth Colomb, who was of Huguenot descent. He grew up with his elder brother Wilhelm, the later linguist and education reformer. Both boys were taught by private tutors; their father died in 1779.

Humboldt studied at Frankfurt an der Oder and Göttingen, among other places, and attended the mining academy at Freiberg in 1791–1792. From 1792 to 1796 he worked as a Prussian mining official. After his mother's death in 1796 his inheritance allowed him to finance a long voyage; his planned participation in a voyage around the world under Nicolas Baudin did not take place.

In 1799 Humboldt left Spain with the French botanist Aimé Bonpland, with permission from the Spanish crown, and arrived at Cumaná. Over five years they travelled through present-day Venezuela, Cuba, Colombia, Ecuador, Peru and Mexico. In 1800 they explored the Orinoco and the Casiquiare; that link with the Amazon basin had been established decades earlier, but Humboldt determined the exact position of the bifurcation.

On 23 June 1802 Humboldt, Bonpland and Carlos Montúfar climbed Chimborazo. Humboldt himself calculated that they reached about 5,900 metres; reconstructions by later mountaineers suggest about 5,600 metres, below the summit at 6,263 metres. From his observations he showed vegetation zones, temperature and air pressure by altitude in his Naturgemälde, which appeared in 1807.

After his return Humboldt worked up his data in Paris. He wrote the essay on the geography of plants (1807), the Political Essay on New Spain and a study of Cuba, and in 1817 introduced isotherms, lines of equal mean temperature. In 1829 he travelled at the invitation of the Russian government to the Urals, Siberia and the Altai Mountains; his Kosmos began to appear in 1845.

Humboldt was a child of the Enlightenment and German Romanticism. He was in contact with Goethe and Schiller and combined precise measurements with the conviction that nature forms a coherent whole. His voyage was made possible by an exceptional permission from the Spanish crown, which generally restricted access to its colonies for foreign travellers.

His years of travel fell just before the wars of independence in Spanish America. He wrote critically about colonial inequality, labour in the mines and slavery, for example in his essay on Cuba (1826). At the same time his work relied on colonial infrastructure and on the knowledge of Indigenous guides, local scholars and porters.

Humboldt's publications made the European public familiar with Spanish America and were also read in Latin America. He probably met Simón Bolívar in Paris in 1804 and again in Rome in 1805; that he inspired Bolívar to join the independence struggle cannot be demonstrated. In 1804 he shared data on New Spain with President Jefferson.

His method of comparing measurements over great distances influenced biogeography, climatology and research on terrestrial magnetism. He also pointed to the effects of deforestation and agriculture on climate, for example at Lake Valencia in Venezuela (1800). Darwin named Humboldt's Personal Narrative as an inspiration; Haeckel, Muir and Thoreau were also influenced by him.

Humboldt died on 6 May 1859 in Berlin, aged 89, and was buried with state ceremony on the family estate at Tegel. His Kosmos (1845–1862) aimed to bring knowledge of nature, from the cosmos to the earth, together in one work. Opinions differ on the importance of that work; some regard his travel narratives and the essay on New Spain as more significant.

Many places, species and institutions bear his name, such as the Humboldt Current along the west coast of South America. Recent historians highlight both his scientific contribution and the colonial context of his journeys: his criticism of slavery and colonial rule, but also his dependence on local knowledge, which according to some researchers was not sufficiently acknowledged.