Juan Guaidó has just sworn himself in as the president of Venezuela. He mobilized tens of thousands of his supporters. And won the backing of a powerful ally, the Trump administration. But how did Guaidó go from virtually unheard of to a U.S. supported opposition figure? The 35-year-old got involved in politics as a student leader in Caracas. He led protests against then-president Hugo Chávez. But it wasn’t until earlier this month when he was sworn in as the new leader of the National Assembly that Guaidó became a household name. President Nicolás Maduro tried to dissolve the National Assembly in 2017 and has since sidelined the legislative body. But Guaidó has been outspoken in his defiance. He was briefly detained on Jan. 13 by Venezuela’s intelligence service. He relayed his experience to his supporters. Guaidó called on Venezuelans to come out and protest on Jan. 23 in an effort to get rid of Maduro. “Hola. I’m Mike Pence.” Vice President Mike Pence has voiced his support for Guaidó and the opposition. “The United States supports the courageous decision by Juan Guaidó, the president of your National Assembly, to assert that body’s constitutional powers, declare Maduro a usurper.” This is how Maduro responded to the administration’s support of his rival. However, there is no indication that Maduro is going to resign. Canada and the Organization of American States have also joined in recognizing Guaidó as the legitimate head of state. Guaidó has launched the most direct challenge to Maduro’s government so far, with thousands of people and the U.S. government at his side.