Corbin practiced law in his hometown until 1851, when he moved to
Davenport, Iowa. In 1854, he became a partner of the Macklot & Corbin banking firm, the only bank in Davenport to not suspend payments in the
1857 financial panic. This success set him up to start the first national bank, when his cousin, Secretary of the Treasury
Salmon P. Chase, established the national banking system early in the
Civil War. By 1865, when Corbin moved to New York City, he was considered wealthy. However, the plan never materialized, as the planned port at
Fort Pond Bay in Montauk could not be dredged to handle the seagoing vessels. Corbin's tactic included the infamous strong-arming (along with his cohorts) of the
Montaukett tribe out of nearly they owned around Montauk. The tribe is still seeking compensation for this tactic. Relics from the tribe are still visible at
Camp Wikoff which the LIRR sold the government and where
Theodore Roosevelt and his
Rough Riders were quarantined after returning from the
Spanish–American War. Corbin acquired the
Sunnyside Plantation in
Chicot County, Arkansas, from
John C. Calhoun II, the grandson of
John C. Calhoun and brother of
Patrick Calhoun, in 1886. In 1894, he entered into an agreement with the state of Arkansas whereby he was given 250 convict laborers to pick cotton for him; the profits were shared between Corbin and the state. ==Personal life==