List of Famous people born on December 20th

Ottavio Farnese was an Italian nobleman. He was an illegitimate son of Ranuccio I Farnese, Duke of Parma and Briseide Ceretoli, who was at that time unmarried; she was the daughter of Ottavio Ceretoli, a captain who had died in Flanders in the following of Alessandro Farnese, Duke of Parma. The couple also had an illegitimate daughter, Isabella.

Duke Alexander of Württemberg was a member of the dynasty which ruled the German kingdom of Württemberg. To marry a daughter of the French king he agreed that their children would be raised in their mother's faith, thereby becoming ancestor of the Roman Catholic branch of his family.

Jaroslav Heyrovský was a Czechoslovak chemist and inventor. Heyrovský was the inventor of the polarographic method, father of the electroanalytical method, and recipient of the Nobel Prize in 1959 for his discovery and development of the polarographic methods of analysis. His main field of work was polarography.

Hideki Niwa is a Japanese politician of the Liberal Democratic Party (LDP), a member of the House of Representatives in the Diet. A native of Kasugai, Aichi and graduate of Tamagawa University he was elected for the first time in 2005 after an unsuccessful run in 2003.He was defeated in the 2009 election by DPJ candidate Yoshihiro Ishida.

Rambai Barni, formerly Princess Rambai Barni Svastivatana, was the wife and Queen Consort of King Prajadhipok of Siam.