A Guide to the United States’ History of Recognition, Diplomatic, and Consular Relations, by Country, since 1776: Liechtenstein
Although the United States has long maintained good relations with Liechtenstein, Liechtenstein yielded control of its foreign affairs to Switzerland for much of the twentieth century. Therefore, direct diplomatic connections between Liechtenstein and the United States are of relatively recent origin. Liechtenstein began pursuing independent membership in international organizations at the end of the twentieth century. The United States first accredited its Ambassador to Switzerland to serve Liechtenstein in 1997.
U.S. Recognition of Liechtenstein, 1926.
Formerly a part of the Holy Roman Empire, Liechtenstein achieved sovereignty in 1806, joined the German Confederation in 1815, and became independent again in 1866. The United States executed its first treaty with Liechtenstein in 1926, although Liechtenstein was represented in foreign affairs at the time by Switzerland. Because Switzerland and Liechtenstein allowed free passage between their two countries, an exchange of notes between the Swiss and U.S. governments extended rights of a U.S.-Swiss agreement to include citizens of Liechtenstein as well.