Justin Amash
The first Libertarian to hold a seat in the U.S. Congress. He served in the House of Representatives as the U.S. Representative for Michigan from January 14, 2009 to January 12, 2011 and from January 3, 2011 – January 3, 2021. In the Summer of 2019, he officially left the Republican party due to the issues they observed being caused by the two party system in the Federal government. In April 2020, he changed his political designation from independent to Libertarian.
Justin Amash was the first Libertarian to hold a seat in the U.S. Congress, which was a very big deal because of how it helped challenge the two mainstream parties control over congress.