An impresa (plural imprese) is a variant of the badge which became particularly popular in the 15th and 16th centuries. The one below is the impresa of Piero dei Medici.
This next one is the sole raggiante, or ragged sun, of the Sforza. You can also see and read more on Sforza imprese here: http://www.storiadimilano.it/arte/imprese/Imprese05.htm
Here is a photo of the sole raggiante on the Duomo of Milan.
Pastoureau (in his Traité d’Héraldique, 2 ed., pp. 218-9) states that the use of figures such as an animal, plant or object, to symbolize an individual or lineage is quite ancient and preceded heraldry (e.g., the broom plant of the Plantagenet); eclipsed by heraldry, it made a come-back in the 14th c. and gained great importance, perhaps as a way to individualize what had become a fairly formal and rigid system.
Starting in the 15th c. the badge was often accompanied by a short motto, and this gave rise to what are called in Italian impresa (plural: imprese), in which a figure called the body of the badge is combined with a motto (in Italian, “word”) called the soul, usually the former illustrating the latter, the latter explaining the former, both alluding to the individual who chose them. These were very popular in the 15th-17th c. in Italy and by imitation in France, but also elsewhere. In the 16th c. books were written on the subject of imprese, such as Ercole Tasso: Della realta e perfettione delle Imprese, and Paolo Giovio: Ragionamento delle Imprese; providing rules on how to compose them and listing examples. Giovio’s rules are:
- adequate correspondance of body and soul (figure and motto),
- neither obscure nor too obvious,
- pleasing appearance,
- no human form,
- the motto not be in the vernacular of the person who chose the impresa, and brief without being ambiguous.
Imprese were sometimes used by a whole family, but many times they were individual, and indeed the same individual might have several at the same time or in succession.
Some available references, in Italian and French, can be found by typing the name of these books or author in the search engine of the Bibliotheque nationale de France or at the awesome Internet Archive (the archive tends to have better facsimiles):
- Andrea Alciato: tratte de gli emblemi (1549)
- Scipione Bargagli: Dell’imprese (1594)
- Giovanni Ferro: Teatro d’imprese (1623)
- Paolo Giovio: Ragionamento sopra i motti, e disegni d’arme, e d’amore, che communemente chiamano imprese (1556)
- Jeronimo Ruscelli: Le impresse illustri (1583)
- Gabriello Simeoni: Le sententiose imprese (1560)
- Adrian d’Amboise: Devises royales (1621)
- François d’Amboise: Discours ou traicté des devises (1620)
- Pierre Lemoyne: De l’Art des devises (1666)
- Alphonse Chassant, Henri Tausin: Dictionnaire des devises historiques et héraldiques (1878-95): vols. 1, 2, 3, and Suppl.
volumes 1 and 2 list mottoes from A to Z and the families who used them; volume 3 provides an index of family names; families are from all over Europe. No translations are provided.
Taken from http://www.heraldica.org/topics/imprese.htm, please read more there!