The opening of Newgate of Connecticut, situated in an abandoned copper mine in the central part of the colony of Connecticut, anticipated the Jail by almost 20 years. The Connecticut General Assembly authorized the prison in 1773, and it was opened in December of the same year. In view of the general colonial reluctance to punish serious crime with incarceration, the opening of the prison is a significant event. This paper describes the origination of Newgate and its effectiveness in achieving its objectives during its initial year of operation. In addition, the analysis considers Newgate in the context of the major explanatory perspectives in penological theory. The analysis suggests that the origination of Newgate is not explained well by these perspectives, but seems rather to be the result of colony- and period-specific influences operating in Connecticut during the 1770's.