United States senator Nelson Wilmarth Aldrich (1841-1915) was the ablest of a group of Republican conservatives who fought a rearguard action against progressivism during the administrations of Theodore Roosevelt and William Howard Taft.

A descendant of Roger Williams, Nelson Aldrich was born in Foster, R.I., on Nov. 6, 1841, and educated in the common schools of the area. His marriage to Abby Chapman in 1865 brought him a measure of wealth and gave him entry to society, but he was essentially a self-made man. After service in the Civil War, he rose to partnership in a wholesale grocery business. He invested shrewdly and ultimately became one of Rhode Island's foremost financiers.

A resourceful leader, Aldrich was a man of extraordinary charm, lucidity, and willpower. He served two terms in the Rhode Island Legislature and one in Congress before being elected to the U.S. Senate in 1881. There for 30 years he...