Which order was called the Knights of the Tau?

The Order of Saint James of Altopascio also called the Knights of the Tau was a military order, perhaps the earliest Christian institution to combine the protection and assistance of pilgrims, the staffing of hospitals, and a military wing. According to American historian Ephraim Emerton, who produced the first systematic study of the Order, "the fame of the house drew visitors, both well and sick, including women in childbirth and infants" from around Italy.