March 1 was, in the pre-Julian calendar, the first day of the Roman year. On this day, moreover, Roman religion celebrated Matronalia (or Matronales Feriae), a festival dedicated to Roman matrons.
According to tradition, the festival was established by Romulus himself and Titus Tatius, king of the Sabines, in order to celebrate the Sabine women who, after being abducted by the Romans in the so-called "Rape of the Sabine Women", contributed to the peace between the two people. The festival then developed into a celebration of Juno Lucina, the goddess of mothers and childbirth, whose temple on the Esquiline Hill was built on March 1, 375 BC. Roman women, who were exceptionally allowed to wear their hair loose, were thus expected to offer incense and flowers to Juno's temple, where they would also pray for the glory of their husbands; in return, men were to give presents to their wives and mothers. Household slaves, being given the day off, would also be offered a meal prepared by the matron herself.
"Juno", illumination from the manuscript "Le romant des Fables Ovide le Grant", ms. 5069 réserve, f. 17r, 1301-1325, Bibliothèque nationale de France, Paris.