It has been argued, however, that the sheer number of Irish speakers in the nineteenth century and their social diversity meant that both religious and secular authorities had to engage with them. This meant that Irish, rather than being marginalised, was an essential element in the modernization of Ireland, especially before the Great Famine of the 1840s. Irish speakers insisted on using the language in the law courts (even when they knew English), and it was common to employ interpreters. It was not unusual for magistrates, lawyers and jurors to employ their own knowledge of Irish. Fluency in Irish was often necessary in commercial matters. Political candidates and political leaders found the language invaluable. Irish was an integral part of the "devotional revolution" which marked the standardisation of Catholic religious practice, and the Catholic bishops (often partly blamed for the decline of the language) went to great lengths to ensure there was an adequate supply of Irish-speaking priests. Irish was widely and unofficially used as a language of instruction both in the local pay-schools (often called hedge schools) and in the National Schools. Down to the 1840s and even afterwards, Irish speakers could be found in all occupations and professions.