around the year 1000, an event in northern india, about the time of muslim invaders, likely triggered their mass exodus. the precise event is still unknown, but the possible reasons include a conflict that resulted in the roma's persecution, a natural disaster, or even recruitment into a mercenary military. the roma journeyed towards the caucasus and china, as well as through the middle east and greece towards the balkans; they covered all corners of today's central and western europe by the end of the 16th century. the roma typically traveled in patriarchal extended families, consisting of up to hundreds of people. during colonial times, some european countries dealt with the roma by shipping them overseas, mainly to various caribbean islands and the present-day united states. in the 1860s, roma from britain arrived in the u.s., but the largest wave of roma arrived in the early 1900s.