Paul Davis Ryan (born January 29, 1970) is an American politician who served as the 54th speaker of the United States House of Representatives from 2015 to 2019. A member of the Republican Party, he was the party's vice presidential nominee in the 2012 election running alongside Mitt Romney, losing to President Barack Obama and Vice President Joe Biden.

Ryan is a native of Janesville, Wisconsin, and graduated from Miami University in 1992. He spent five years working for Congress in Washington, D.C., becoming a speechwriter, then returned to Wisconsin in 1997 to work at his family's construction company. He was elected to Congress to represent Wisconsin's 1st congressional district the following year, replacing Mark Neumann, who had vacated the seat to run for U.S. Senate. Ryan went on to represent the district for 20 years. He chaired the House Budget Committee from 2011 to 2015, and briefly chaired the House Ways and Means Committee in 2015.

A self-proclaimed deficit hawk, Ryan was a major proponent of Social Security privatization in the mid-2000s. During the 2010s, two proposals heavily influenced by Ryan—"The Path to Prosperity" and "A Better Way"—became part of the national dialogue advocating for the privatization of Medicare, the conversion of Medicaid into a block grant program, the repeal of the Affordable Care Act, and significant federal tax cuts. In October 2015, after Speaker John Boehner's resignation, Ryan was elected to replace him. During his speakership, he played a key role in the passage of the Tax Cuts and Jobs Act of 2017 and the Economic Growth, Regulatory Relief and Consumer Protection Act in 2018, which partially repealed the Dodd–Frank Act.

Ryan declined to run for re-election in the 2018 midterm elections. With the Democratic Party taking control of the House of Representatives, Nancy Pelosi succeeded Ryan as Speaker of the House.

Paul Davis Ryan was born on January 29, 1970, in Janesville, Wisconsin, the youngest of four children of Elizabeth "Betty" Ann, who later became an interior designer, and Paul Murray Ryan, a lawyer. He is a fifth-generation Wisconsinite. His father was of Irish ancestry and his mother of German and English descent. One of Ryan's paternal ancestors settled in Wisconsin prior to the Civil War. His great-grandfather, Patrick William Ryan, founded an earthmoving company in 1884, which later became P. W. Ryan and Sons and is now known as Ryan Incorporated Central. Ryan's grandfather, Stanley M. Ryan, was appointed United States attorney for the Western District of Wisconsin. In 2018, while filming a segment for the PBS series Finding Your Roots, Ryan learned that his DNA results included 3 percent Ashkenazi Jewish ancestry.

Ryan attended St. Mary's Catholic School in Janesville, then attended Joseph A. Craig High School, where he was elected president of his junior class, and thus became prom king. As class president Ryan was a representative of the student body on the school board. Following his second year, Ryan took a job working the grill at McDonald's. He was on his high school's ski, track, and varsity soccer teams and played basketball in a Catholic recreational league. He participated in several academic and social clubs including the Model United Nations. Ryan and his family often went on hiking and skiing trips to the Colorado Rocky Mountains.

Although Ryan's father was not a lifelong heavy drinker, staying sober for nearly twenty years after his first stint in rehabilitation, he had become an alcoholic by the time Ryan was a teenager. Ryan later commented on his relationship with his father, whom he revered as a young child, stating that "[alcohol] made him more distant, irritable and stressed ... whiskey had washed away some of the best parts of the man I knew." When he was 16, Ryan found his 55-year-old father lying dead in bed of a heart attack, something Ryan later partially attributed to heavy alcohol consumption. Following the death of his father, Ryan's grandmother moved in with the family. As she had Alzheimer's, Ryan helped care for her while his mother commuted to college in Madison, Wisconsin. From the time of his father's death until his 18th birthday, Ryan received Social Security survivors benefits which were saved for his college education. His mother later married widower Bruce Douglas.

Ryan has a bachelor's degree in economics and political science from Miami University in Oxford, Ohio, where he became interested in the writings of Friedrich Hayek, Ludwig von Mises, and Milton Friedman. He often visited the office of libertarian professor Richard Hart to discuss the theories of these economists and of Ayn Rand. Hart introduced Ryan to National Review, and with Hart's recommendation Ryan began an internship in the D.C. office of Wisconsin U.S. Senator Bob Kasten, where he worked with Kasten's foreign affairs adviser.