This thesis examines crime in nineteenth-century Ireland, with particular focus on female inmates and juveniles. Grangegorman female penitentiary and Richmond male penitentiary are the case studies utilised to carry out this research. Grangegorman penitentiary was the first ever exclusively female prison in the British Isles. This study starts in 1836, with the opening of Grangegorman female penitentiary, and ends in 1860. This enables a pre-Famine, Famine and post Famine analysis of prisons and prisoners in Ireland. The nineteenth century was an era of significant penal reform and the 1826 Irish Prisons Act was a landmark legislation that attempted to regulate prisons. This act advocated "moral reform" as a means of diminishing crime. The prisons in Ireland during the period 1836-60, were predominately filled with the lower classess and thus "moral reform" was a failure as poverty and not immorality was the prevailing cause of crime at this time. The "separate system" was only introduced to a limited degree in Grangegorman penitentiary during this era, and it failed to deter inmates sufficiently from re-offending as there was a high rate of recidivism among inmates there. there was a high number of mentally ill inmates, juvenile offenders, as well as non-criminal children who were received into prison with their mothers, in Grangegoram and throughout the Irish prison between 1836 and 1860. These groups cannot be overlooked. Juveniles gradually became a distinct social group during this time. It was slowly accepted by the authorities that juveniles did not belong in an adult penitentiary, and a different discipline system had be developed for them. Destitute children were seen as predisposed to crime and thus concern with their conduct developed also. This research also offers a comparative analysis of female and male prisoners by comparing the treatment of male inmates in Richmond penitentiary with afforded female inmates in Grangegorman penitentiary. Overall this thesis offers a comprehensive insight into prisons and prisoners in nineteenth-century Ireland.