Jack Alan Markell (born November 26, 1960) is an American politician and businessman who is the United States ambassador to Italy and San Marino since 2023. Markell was the United States Ambassador to the Organisation for Economic Co-operation and Development from 2022 to 2023. He was the Governor of Delaware from 2009 until 2017. Markell was a member of the Democratic Party. He was the State Treasurer of Delaware from 1999 to 2009.
In June 2021, President Joe Biden nominated Markell to be the U.S. Ambassador to the OECD. His nomination was confirmed by the United States Senate on December 18, 2021.
On May 12, 2023, President Joe Biden nominated Markell to serve as the United States ambassador to Italy and San Marino. He was confirmed by the full Senate to this position on July 27, 2023.