The first ‘modern’ passports date from 1915, but circa 1850 passports became standardized documents used by nationals to travel abroad. They began life as a single sheet of paper, but by 1915 had also begun to include a photograph. Application records for passports found here can provide great detail about the individual applicant, as well as the knowledge that your ancestor likely travelled abroad at some point – which may lead to new lines of enquiry.