William Nelson Cromwell (January 17, 1854 – July 19, 1948) was an American attorney active in promotion of the Panama Canal and other major ventures especially in cooperation with Philippe Bunau-Varilla.He was born and raised in Brooklyn, New York, in an Episcopalian household, by his mother, Sarah M. Brokaw, a Civil War widow. His father, John Nelson Cromwell, died in the Battle of Vicksburg. He worked as an accountant for the attorney Algernon Sydney Sullivan, who paid for his education at Columbia Law School and made him a partner in Sullivan & Cromwell in 1879. In 1898 the chief of the French Canal Syndicate (a group that owned large swathes of land across Panama), Philippe Bunau-Varilla, hired him to lobby the US Congress to build a canal across Panama, and not across Nicaragua, as rivals would have it. Cromwell showed that Nicaragua had an active volcano. On June 19, 1902, three days after senators received stamps showing volcanic activity in Nicaragua they voted for the Panama route for the canal. For his lobbying efforts, he received the sum of $800,000. (about 30 million USD today). After the Hay–Bunau-Varilla Treaty was ratified, Cromwell was paid another $2,000,000 (about 70 million USD today) – at the time, the highest amount ever paid to a lawyer.