What era in art is this?
This was made late in the Medieval period, right before the Renaissance began.
How does this differ from Byzantine art?
It's actually quite similar. Painting styles in Medieval Italy were strongly based on Byzantine precedents, especially the use of gold ground and standardized depictions of Christian religious figures. The beginning of the Italian Renaissance is characterized by a return to Classical standards in art especially a closer attention to realism in the human form.
The Byzantine, or Eastern Roman Empire was centered in modern day Istanbul and existed from the 4th to the 16th century. It was an important early seat of Christianity and many religious artistic standards were set there.
Ohhh
This seems like the darkest blue I’ve ever seen on any Madonna, and darker than the other blues on the piece itself - is this intentional or maybe related to the aging of the work?
The darkness of the blue as it appears today is definitely related to the aging of the piece. It always would have been somewhat darker than the blues you see the male figures wearing, though, it was made with a different pigment.
The artist was interested in portraying a difference between the Madonna and the other figures. He would have used a different pigment to paint a deeper blue for her mantle. Ultramarine (one of the most expensive pigments at the time) and similar shades were reserved for the Madonna and other figures held in the highest esteem.
Why is this piece called Madonna of Humility?
"Madonna of Humility" refers to the way that the Madonna is depicted here, sitting in a grassy garden instead of enthroned. It is meant to present here as a humble and (importantly) relatable mother.
The Madonna of Humility type was especially popular for private devotion as opposed to an image of the Madonna enthroned as the queen of heaven as you might see in altarpieces designed for cathedrals.
Why does the baby look like an adult?
The Christ child does look very grown up, doesn't he? This may be to show that he had a special divine role to play. It is also important to remember that artists at this time typically did not sketch babies from life. Things often look a little unusual when you have to sketch only from memory.
Can I get some more information on the "Madonna of Humility"?
This is a small and portable altarpiece. It was meant for personal devotion in the home, private family chapel, or in the cells of monks and friars, as required.
Altarpieces helped individuals to engage quietly with beloved saints on an intimate, emotional level, rather than the communal ritual of Mass.
The central panel shows the Madonna of Humility, a popular way of portraying the Virgin Mary in the later Middle Ages and early Renaissance. She is seated humbly on the ground, holding the Christ child in her lap. The delicate fringe of grasses and flowers below the Madonna of Humility indicates that she is in a garden, a traditional symbol of the Virgin.