Hiya sunseeker,
1659 'Pender's Census':This was compiled by Sir William Petty who also was responsible for the Civil Survey. There are a number of problems in using the 1659 Census as a source of data. It was based on a poll tax so it is not a full ‘census’ of the population at the time. It only lists the number of adults paying tax ... ie it records the names of persons with title to land (tituladoes), the total numbers of English and Irish living in each townland and the principal Irish names in each barony. Five counties, Cavan, Galway, Mayo, Tyrone and Wicklow, are not covered. The work was edited by Seamus Pender and published in 1939. (See reference NLI I 6551 Dublin).
The University College, Cork ...
Documents of Ireland contains an interesting article on the 1659 Census.
Christopher