Commissioned in 1932, Route 191 originally included only Broadbrook Road, connecting Route 140 and Route 190. This was formerly state highway 208.

In 1941, Route 191 was extended 4.6 miles west along North Street, to end at US 5. This segment is now part of Route 140.

On July 3, 1961, during a rerouting triggered by the opening of the Bradley Airport Connector on Route 20, Routes 140 and 191 swapped segments to arrive at their locations today.

Route 191 Ends (Photos; Doug Kerr at state-ends.com)