On February 4, 1863, at the Back Bay residence of financier Samuel Gray Ward, an organizing committee of fifteen was formed with the mandate to found a new club for Boston’s economic and social elite. By February 27 they had a clubhouse at 8 Park Street, and by year's end, 512 members.

 

“The state of feeling [at the Somerset] was more conspicuously critical than patriotic,” wrote Martin Brimmer. “Some privately denounced the war in all its aspects; some attacked indiscriminately all acts of the government…; some were indifferent; some were wavering; some, with the best of intentions, were made doubtful and timid by the tone of people about them. For those, and there were happily many of them, who were unhesitating in their support of the war, there was not common centre, no rallying place." Brimmer, Ward, Forbes, and others set out to found a club where “gentlemen could pass an evening without hearing copperhead talk,” but more importantly to consolidate and maintain cohesion among the members of the bourgeoisie and leading intellectuals who to varying degrees were behind the war and Lincoln’s war measures. Six of the twenty-eight-member executive committee had been members of the Somerset since its founding in 1852.

 

The Union Club's membership was only open to "clubbable men" by invitation of the Committee on Elections.