The United States government shut down for the eighteenth time in modern history on Saturday, January 20th. The reason behind the shutdown was an inability to reach a bipartisan agreement on Congressional funding.
It should be noted that Republicans control the House, Senate, and the Presidency, but were still not able to pass a bill in the Senate. Per the Washington Post: “A government shutdown causing employee furloughs has never occurred under unified party control of Congress and the White House. Some furloughs of White House employees began immediately early Saturday.”