Costello Converse was born in Jamaica Plain, MA in 1848 to James Wheaton Converse and Emmeline Coolidge Converse. He had one sibling: Emma Maria Converse. In 1882, he married Mary Ida Converse, his first cousin, daughter of Elisha Slade Converse and Mary Diana Edmands Converse. They had one son, Costello Ide Converse, who sadly passed away 2 days after his birth in 1883. He established a number of trusts for his nieces and nephews and their issue, some of which are still in effect.

He worked with his father, James Wheaton Converse, in several family businesses in Grand Rapids, Michigan, primarily the Grand Rapids Plaster Company and the Phoenix Furniture Company. There was also a clothespin factory on the West Side, which was rolled into the Converse Manufacturing Company, along with factories in Newaygo. He then became involved with the Boston Rubber Shoe Company, as vice president and director, as well as several other rubber manufacturing companies.

Costello and Ida funded the Converse Wing of New England Baptist Hospital. They gifted The Skinner Organ to the First Baptist Church in Malden, MA., one of the finest instruments of its kind in the U.S. Northeast. Costello gifted a magnificent Casavant organ with 6,000 pipes (making it the largest in the U.S. at the time) to the Tremont Temple in Boston, which was rebuilt after an 1893 fire.

His Obituary from The Boston Globe on Nov. 30, 1931 reads as follows:

“Costello C. Converse, aged 83, long connected with manufacturing, industrial and banking interests of Boston, died this morning at his home, 348 Beacon St., Back Bay.

Mr. Converse was born in Jamaica Plain and was educated in the Chauncy School. He is survived by his wife, formerly Miss M. Ida Converse of Malden, whom he married in 1882.

Mr. Converse was born on Sept. 22, 1848, the son of James W. and Emeline C. Converse. His wife is the oldest daughter of the late Hon. Elisha S. Converse of Malden. Mr. Converse’s father, the late Deacon (James) Converse, was for many years the largest stockholder in the Boston Rubber Shoe Company, with whom his son, Costello Coolidge Converse, afterward became connected.

His town house was at 348 Beacon St. The doorway of the house, designed for Mr. Converse, is Romanesque in style, with elaborate carved arch and impost supports that closely follow that style. For many years he has had an attractive waterfront summer place at Magnolia, on the North Shore.

Mr. Converse was president and director of the Grand Rapids Plaster Company, director of the Mutual Insurance Company, a trustee of the Malden Hospital, director of the Rubber Manufacturers’ Mutual Insurance Company, director of the Associated Charities of Malden, director of the Children’s Friend Society and vice president and director of the Cotton and Woolen Manufacturers’ Mutual Life Insurance Company.

Below is a listing of additional professional endeavors, which were many. In addition, he was treasurer of the Boston Cold Storage and Freezing Company before assuming his father James Converse’s interests in the Boston Rubber Shoe Company.