The <a href="https://en.wikipedia.org/wiki/Missouri_Compromise" id="mwXA" rel="mw:WikiLink" title="Missouri Compromise">Missouri Compromise</a> is signed into law by President <a href="https://en.wikipedia.org/wiki/James_Monroe" id="mwXQ" rel="mw:WikiLink" title="James Monroe">James Monroe</a>. The compromise allows <a href="https://en.wikipedia.org/wiki/Missouri" id="mwXg" rel="mw:WikiLink" title="Missouri">Missouri</a> to <a href="https://en.wikipedia.org/wiki/Admission_to_the_Union" id="mwXw" rel="mw:WikiLink" title="Admission to the Union">enter the Union</a> as a <a href="https://en.wikipedia.org/wiki/Slave_states_and_free_states" id="mwYA" rel="mw:WikiLink" title="Slave states and free states">slave state</a>, brings <a href="https://en.wikipedia.org/wiki/Maine" id="mwYQ" rel="mw:WikiLink" title="Maine">Maine</a> into the Union as a <a href="https://en.wikipedia.org/wiki/Slave_states_and_free_states" id="mwYg" rel="mw:WikiLink" title="Slave states and free states">free state</a>, and makes the rest of the northern part of the <a href="https://en.wikipedia.org/wiki/Louisiana_Purchase" id="mwYw" rel="mw:WikiLink" title="Louisiana Purchase">Louisiana Purchase</a> territory slavery-free.