In 1766, Gershom Mendes Seixas became the leader of Shearith Israel, New York City's first and oldest Spanish and Portuguese (Sephardi) congregation, and remained its minister for about a half century. Although not ordained as a rabbi, Seixas served as hazzan and religious leader to the congregation and was among the first leaders of the Jewish community who had been born and educated in the United States. As the British fleet approached New York Bay in August, 1776, Seixas preached an emotional sermon in English, warning that that day's services might be the last held in the historic edifice. His Patriot loyalties provoked Shearith Israel to seal its entrance as the British approached, and Mendes Seixas left New York rather than remain under British rule. He rescued the scrolls of the Law and other ceremonial items as he fled for Stratford, Connecticut, where several members of the congregation joined him. In 1780, patriots who had fled to Philadelphia wanted to establish the city's first permanent congregation and selected Mendes Seixas to officiate. He thus helped establish historic Congregation Mikveh Israel. Many important politicians attended the synagogue's dedication, including the governor of Pennsylvania, and Seixas invoked "the blessings of Almighty God on the Members of these States in Congress assembled and on his Excellency George Washington, Commander-General of these Colonies".