Due to a special event taking place in the U.S. Capitol on Thursday, September 18, there will be no tours of the U.S. Capitol that day until approximately noon. The Capitol Visitor Center will remain open during this time, and guided tours in the Capitol Visitor Center will be available.
For much of the first half of the 19th century, there was a balance in Congress between Northern free states and Southern slave states. In 1836 Texas, which permitted slaveholding, declared independence from Mexico and sought annexation to the United States. Mexico threatened war over U.S. annexation of Texas, and in Congress the issue of annexation inflamed debate regarding slavery’s expansion. After the Senate rejected an annexation treaty, Congress annexed Texas in 1845 by a joint resolution and declared war with Mexico the following year.