La The church of Saint Francis is home to many paintings dating back to different historical periods, which confirm the strong bonds of the Order of Friars Minor with Mary and clearly illustrate the evolution of Marian iconography in time. The oldest image of the Blessed Virgin is a fresco taken from the friary walls and currently found in the Martinozzi Chapel in the right wing of the transept. The work, painted by Sienese artist Lippo Vanni in the second half of the fourteenth century, recreates the structure of a polyptych: The Blessed Virgin with Child, together with four Saints, are in the centre; above there is the Blessing Christ with the four Fathers of the Church, while the predella portrays a Pietà, with Christ cradled by Mary and St. John, flanked by figures of prophets.The Blessed Virgin holds the Child who embraces her lovingly while playing with his Mother’s veil. This representation of the Blessed Virgin, known as "Eleousa", the Merciful, is one of the oldest and most popular ones in the Middle Ages. The artist lays emphasis on the human side of the two figures: Jesus is portrayed as a lively child who looks straight at the observer, while the Blessed Virgin’s tightened lips and melancholy gaze echoes her awareness of her Son’s tragic fate.
However the Virgin and Child are not always depicted in such a natural manner; sometimes artists gave them a regal stance, as in the panel painted in 1398 by a painter influenced by Andrea Vanni, and now placed in the first chapel to the right of the High Altar, formerly under the patronage of the Palmieri family. The Blessed Virgin’s seating is covered by a red cushion, a sign of royalty, and the back is decorated with a blue, red and gold chequered drape. The figures stand out against the golden background that represents the light brought into the world by the Resurrection of Christ. Mother and Son look at the viewer in an almost identical pose to the one they have in another masterpiece of the Sienese artist: The Maestà by Duccio di Buoninsegna made between 1308 and 1311 for the city’s cathedral. Mary is swathed in a blue mantle with a gold star on her right shoulder, symbolising her virginity. The Virgin bestows her Son, who will sacrifice his life to save humanity, to the world. The painting was severely damaged by the fire that ravaged the church in 1655, and was restored in 2005 by the Circolo degli Uniti di Siena.
To conclude, the last chapel of the left wing of the transept contains a painting of the Virgin and Child. The fresco, painted by Jacopo di Mino in the late fourteenth century, portrays the Virgin seated on an architectural throne, enveloped in an ample blue cloak fastened with a gold buckle on her bosom. The Infant Christ, wrapped in elegant pink garments, sits in his Mother's arms, clutching her hand with his left hand while he gives a blessing with his right hand. Our Lady’s face is framed by an embossed golden halo, similar to the one surrounding the Child’s head, which is decorated with a red inscribed cross.