Theodore Roosevelt signs the Antiquities Act into law, authorizing the President to restrict the use of certain parcels of public land with historical or conservation value.

Theodore Roosevelt Jr., also known as Teddy or T. R., was the 26th president of the United States, serving from 1901 to 1909. Roosevelt previously was involved in New York politics, including serving as the state's 33rd governor for two years. He served as the 25th vice president under President William McKinley for six months in 1901, assuming the presidency after McKinley's assassination. As president, Roosevelt emerged as a leader of the Republican Party and became a driving force for anti-trust and Progressive Era policies.

The Antiquities Act of 1906 is an act that was passed by the United States Congress and signed into law by Theodore Roosevelt on June 8, 1906. This law gives the president of the United States the authority to, by presidential proclamation, create national monuments from federal lands to protect significant natural, historic, or scientific features. The Act has been used more than a hundred times since its enactment to create a wide variety of protected areas.

In all modern states, a portion of land is held by central or local governments. This is called public land, state land, or Crown land. The system of tenure of public land, and the terminology used, varies between countries. The following examples illustrate some of the range.