Holland, Howland
Holland, Howland—These two names are the anglicised forms of O'Houlahan in the Isle of Man, and both names are found in the maritime counties on the adjoining English Mainland, in Gaelic O' h-Uallachain.
Alphabetical Index of Anglicised Surnames in Ireland
See also Woulfe’s Irish Names and Surnames
… and O'Hart's Irish Pedigrees