Matthias Schleiden is credited, along with Theodor Schwann, with articulating the cell theory. Born in Hamburg, he began his career as a lawyer. He met with no great success in law, and, becoming increasingly depressed, attempted suicide. After recovering from the failed attempt, he returned to school to study medicine, specializing in botany.

Schleiden served as a professor first at Jena and later at Dorpat, then resigned and moved frequently from town to town until he died in 1881. Possibly as a result of his previous career, Schleiden was impulsive, sharp and scornful of his opposition. He rejected the botanist as a glorified scientific librarian, opting for a focus on the anatomy and physiology of plants. "Most people of the world, even the most enlightened," he said, "are still in the habit of regarding the botanist as a dealer in barbarous Latin names, as a man who gathers flowers...