Hans Christian Joachim Gram was a Danish physician and bacteriologist who developed a method of staining cells for microscopic study. Gram was born in Copenhagen, Denmark, on September 13, 1853. He received a B.A. in the natural sciences from the Copenhagen Metropolitan School in 1871 and served as an assistant to the zoologist Japetus Steenstrup from 1873-1874. He subsequently became interested in medicine and earned a medical degree from the University of Copenhagen in 1878. Gram, who worked in several areas of science and medicine, earned a gold medal in 1882 for a study on human erythrocytes. The following year he received a doctoral degree for his work in this field.

After obtaining his degree, Gram pursued post-doctoral studies in Berlin, focusing on bacteriology and pharmacology and pursuing post-doctoral studies in Berlin. It was in Berlin, in 1884, that he published his work on staining cells, which became widely known as Gram staining...