George Washington
At the end of his second term, Washington retired for personal and political reasons, fatigued and disgusted with personal attacks, and to assure a truly contested presidential election could be held. He did not feel bound to a two-term limit, but his retirement ultimately set precedent. The two-term limit to the presidency was formalized with the 1951 adoption of the Twenty-second Amendment to the United States Constitution. Washington is often credited with setting the principal of a two-term presidency, but it was Thomas Jefferson who first refused to run for a third term on political grounds.
President of Liberia
Under the original 1847 Constitution, the president was elected to a two-year term, which was increased to four years on May 7, 1907. Under this amendment, a new president would serve for eight years and could be re-elected to unlimited four-year terms. During the presidency of William Tolbert, the Constitution was amended to restrict the president to a single eight-year term; by 1976, voices in the Legislature were being raised in favor of returning to the previous system, but Tolbert proclaimed his support for the existing system and vowed to veto any constitutional amendments to remove term limits.