Carlos Diego Mesa Gisbert is a prominent Bolivian politician, historian, and journalist. He served as the 63rd President of Bolivia from October 2003 until his resignation in June 2005. Before his presidency, Mesa was a well-respected television journalist and historian, co-founding the PAT television network. He has remained an influential figure in Bolivian politics, running for president again in recent years and continuing to be a leading voice in the opposition.