An image from an 18th century book of historical dates, numbers, inscriptions and astronomical events. Printed in Paris, France in 1763. "Tablettes Chronologiques de l'Histoire Universelle, Sacree et Prophane, Ecclesiastique et Civile, Depuis la Creation du Monde justqu'a l'an 1762." by Abbot Lenglet Dufresnoy. Book 1: Ancient History.
The name Martius reminds us that the month was named in honour of the Roman god of war Mars. For a long period of time this month was the first of the calendar until a further two months were added (January and February).
The origin of the month of April - Aprilis - is unclear. It may have been associated to the word meaning "to open", aperire ie with the opening of flowers and buds in spring. The month was traditionally associated with the roman goddess Venus and so it is possible that the name is somehow derived from the name of the goddess of beauty and love.