Year 1456 (MCDLVI) was a leap year starting on Thursday (link will display the full calendar) of the Julian calendar.

Andrea Mantegna (Italian pronunciation: [anˈdrɛa manˈtɛɲɲa]; c. 1431 – September 13, 1506) was an Italian painter, a student of Roman archeology, and son in law of Jacopo Bellini. Like other artists of the time, Mantegna experimented with perspective, e.g., by lowering the horizon in order to create a sense of greater monumentality. His flinty, metallic landscapes and somewhat stony figures give evidence of a fundamentally sculptural approach to painting. He also led a workshop that was the leading producer of prints in Venice before 1500.

Mantegna was born in Isola di Carturo, close to Padua (then part of the Republic of Venice), second son of a carpenter, Biagio. At the age of eleven he became the apprentice of Francesco Squarcione, Paduan painter. Squarcione, whose original vocation was tailoring, appears to have had a remarkable enthusiasm for ancient art, and a faculty for acting. Like his famous compatriot Petrarca, Squarcione was something of a fanatic for ancient Rome: he travelled in Italy, and perhaps Greece, amassing antique statues, reliefs, vases, etc., forming a collection of such works, then making drawings from them himself, and throwing open his stores for others to study. All the while, he continued undertaking works on commission for which his pupils no less than himself were made available.

Saint Sebastian (died c. 288) was a Christian saint and martyr, who is said to have been killed during the Roman emperor Diocletian's persecution of Christians. He is commonly depicted in art and literature tied to a post or tree and shot with arrows. This is the most common artistic depiction of Sebastian; however, he was rescued and healed by Irene of Rome before criticising the emperor and being clubbed to death. He is venerated in the Roman Catholic and Orthodox Churches.

The details of Saint Sebastian's martyrdom were first spoken of by 4th century bishop Ambrose of Milan, in his sermon (number 22) on Psalm 118. Ambrose stated that Sebastian came from Milan and that he was already venerated there in the 4th century.

According to Sebastian's 5th-century Acta Sanctorum, still attributed to Ambrose by the 17th-century hagiographer Jean Bolland, and the briefer account in Legenda Aurea, he was a man of Gallia Narbonensis who was taught in Milan and appointed as a captain of the Praetorian Guard under Diocletian and Maximian, who were unaware that he was a Christian.

Lady Anne Neville (11 June 1456 – 16 March 1485) was Princess of Wales as the wife of Edward of Westminster and Queen of England as the consort of King Richard III. She held the latter title for less than two years, from 26 June 1483 until her death in March 1485. She had just one son, Edward, whom she outlived.

Anne was a member of the powerful northern English Neville family, being the younger daughter of Richard Neville, 16th Earl of Warwick, called in history, "The Kingmaker". As a result of this, she was used to strengthen the alliance between her father and Margaret of Anjou during the dynastic civil wars known as the Wars of the Roses fought between the houses of York and Lancaster.

Lady Anne was born at Warwick Castle, the younger daughter of Richard Neville, 16th Earl of Warwick and Anne de Beauchamp. Throughout her life, she would be used as a political pawn. Much of her childhood was spent at Middleham Castle, one of her father's properties, where she and her elder sister, Isabella, met the younger sons of Richard, Duke of York. The two boys would later become important in the lives of both sisters. The Duke of York's wife, Cecily, was a great-aunt to Anne and Isabella.