Fra Angelico (c 1395 - 1455) was a Dominican friar who ended up in Florence via Cortona and Fiesole. He was very devout, treating painting as a spiritual deed and indeed living out his maxim: "He who does Christ's work must stay with Christ always".

I love this painting because of its peace - I wouldn't be surprised if this is what Heaven looks like! What a simple, uncluttered setting that reflects the pure and simple Mary (who doesn't seem at all freaked out by the arrival of someone with wings landing in her garden). There are no surprised expressions, no dramatic waving of arms nor ruffling of the folds in the garments - it is as if Fra Angelico is saying

Mary is in her traditional blue, a colour that has been associated with royalty, peace, and nature (sea and sky): it thus makes sense to clothe "the Queen of Heaven and Earth" in it. The custom dates from around 500 AD when it was also the colour worn by a Byzantine queen. The blue also means that at least part of Mary stands out from contrasting warm colours of the building: a similar colour difference also separates the building from the garden, this adding to the neatness and ordered compartmentalising of the picture. Nature is indeed in its proper place here, tamed, unthreatening, idyllic.