Possibly the swiftest route to your roots.
Irish genealogy website directory.
www.eibhlin.com/portsmouth-genealogy/pintro.html
Description:
This manuscript is a preliminary list of Irish and Irish-Americans (and others) whose headstones are in St. Mary's Catholic Cemetery in Portsmouth, NH, and other Portsmouth records. St. Mary's Cemetery, now called "Calvary Cemetery" was also known as "the Irish Cemetery" in 19th- and early 20th-century Portsmouth.